GUI support for wx, qt and tk.

IPython/frontend/qt/console/scripts/ipythonqt.py

@@ -1,86 +1,92
 #!/usr/bin/env python
 
 """ A minimal application using the Qt console-style IPython frontend.
 """
 
 # Systemm library imports
 from PyQt4 import QtCore, QtGui
 
 # Local imports
 from IPython.external.argparse import ArgumentParser
 from IPython.frontend.qt.console.frontend_widget import FrontendWidget
 from IPython.frontend.qt.console.ipython_widget import IPythonWidget
 from IPython.frontend.qt.console.rich_ipython_widget import RichIPythonWidget
 from IPython.frontend.qt.kernelmanager import QtKernelManager
 
 # Constants
 LOCALHOST = '127.0.0.1'
 
 
 def main():
     """ Entry point for application.
     """
     # Parse command line arguments.
     parser = ArgumentParser()
     parser.add_argument('-e', '--existing', action='store_true',
                         help='connect to an existing kernel')
     parser.add_argument('--ip', type=str, default=LOCALHOST,
                         help='set the kernel\'s IP address [default localhost]')
     parser.add_argument('--xreq', type=int, metavar='PORT', default=0,
                         help='set the XREQ channel port [default random]')
     parser.add_argument('--sub', type=int, metavar='PORT', default=0,
                         help='set the SUB channel port [default random]')
     parser.add_argument('--rep', type=int, metavar='PORT', default=0,
                         help='set the REP channel port [default random]')
     group = parser.add_mutually_exclusive_group()
     group.add_argument('--pure', action='store_true', help = \
                        'use a pure Python kernel instead of an IPython kernel')
-    group.add_argument('--pylab', action='store_true',
-                        help='use a kernel with PyLab enabled')
+    group.add_argument('--pylab', type=str, metavar='GUI', nargs='?', 
+                       const='auto', help = \
+                       "Pre-load matplotlib and numpy for interactive use. If GUI is not \
+                       given, the GUI backend is matplotlib's, otherwise use one of: \
+                       ['tk', 'gtk', 'qt', 'wx', 'payload-svg'].")
     parser.add_argument('--rich', action='store_true',
                         help='use a rich text frontend')
     args = parser.parse_args()
     
     # Don't let Qt or ZMQ swallow KeyboardInterupts.
     import signal
     signal.signal(signal.SIGINT, signal.SIG_DFL)
 
     # Create a KernelManager and start a kernel.
     kernel_manager = QtKernelManager(xreq_address=(args.ip, args.xreq),
                                      sub_address=(args.ip, args.sub),
                                      rep_address=(args.ip, args.rep))
     if args.ip == LOCALHOST and not args.existing:
         if args.pure:
             kernel_manager.start_kernel(ipython=False)
         elif args.pylab:
             if args.rich:
                 kernel_manager.start_kernel(pylab='payload-svg')
             else:
+                if args.pylab == 'auto':
                 kernel_manager.start_kernel(pylab='qt4')
         else:
+                    kernel_manager.start_kernel(pylab=args.pylab)
+        else:
             kernel_manager.start_kernel()
     kernel_manager.start_channels()
 
     # Create the widget.
     app = QtGui.QApplication([])
     if args.pure:
         kind = 'rich' if args.rich else 'plain'
         widget = FrontendWidget(kind=kind)
     elif args.rich:
         widget = RichIPythonWidget()
     else:
         widget = IPythonWidget()
     widget.kernel_manager = kernel_manager
     widget.setWindowTitle('Python' if args.pure else 'IPython')
     widget.show()
 
     # FIXME: This is a hack: set colors to lightbg by default in qt terminal
     # unconditionally, regardless of user settings in config files.
     widget.execute("%colors lightbg", hidden=True)
 
     # Start the application main loop.
     app.exec_()
 
 
 if __name__ == '__main__':
     main()

IPython/lib/pylabtools.py

@@ -1,183 +1,179
 # -*- coding: utf-8 -*-
 """Pylab (matplotlib) support utilities.
 
 Authors
 -------
 Fernando Perez.
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 from IPython.utils.decorators import flag_calls
 
 #-----------------------------------------------------------------------------
 # Main classes and functions
 #-----------------------------------------------------------------------------
 
 
 def find_gui_and_backend(gui=None):
     """Given a gui string return the gui and mpl backend.
 
     Parameters
     ----------
     gui : str
         Can be one of ('tk','gtk','wx','qt','qt4','payload-svg').
 
     Returns
     -------
     A tuple of (gui, backend) where backend is one of ('TkAgg','GTKAgg',
     'WXAgg','Qt4Agg','module://IPython.zmq.pylab.backend_payload_svg').
     """
 
     import matplotlib
 
     # If user specifies a GUI, that dictates the backend, otherwise we read the
     # user's mpl default from the mpl rc structure
     g2b = {'tk': 'TkAgg',
            'gtk': 'GTKAgg',
            'wx': 'WXAgg',
            'qt': 'Qt4Agg', # qt3 not supported
            'qt4': 'Qt4Agg',
            'payload-svg' : \
                   'module://IPython.zmq.pylab.backend_payload_svg'}
 
     if gui:
         # select backend based on requested gui
         backend = g2b[gui]
     else:
         backend = matplotlib.rcParams['backend']
         # In this case, we need to find what the appropriate gui selection call
         # should be for IPython, so we can activate inputhook accordingly
         b2g = dict(zip(g2b.values(),g2b.keys()))
         gui = b2g.get(backend, None)
     return gui, backend
 
 
 def activate_matplotlib(backend):
     """Activate the given backend and set interactive to True."""
 
     import matplotlib
     if backend.startswith('module://'):
         # Work around bug in matplotlib: matplotlib.use converts the
         # backend_id to lowercase even if a module name is specified!
         matplotlib.rcParams['backend'] = backend
     else:
         matplotlib.use(backend)
     matplotlib.interactive(True)
+
+    # This must be imported last in the matplotlib series, after
+    # backend/interactivity choices have been made
     import matplotlib.pylab as pylab
 
+    # XXX For now leave this commented out, but depending on discussions with
+    # mpl-dev, we may be able to allow interactive switching...
+    #import matplotlib.pyplot
+    #matplotlib.pyplot.switch_backend(backend)
+
+    pylab.show._needmain = False
+    # We need to detect at runtime whether show() is called by the user.
+    # For this, we wrap it into a decorator which adds a 'called' flag.
+    pylab.draw_if_interactive = flag_calls(pylab.draw_if_interactive)
 
 def import_pylab(user_ns, import_all=True):
     """Import the standard pylab symbols into user_ns."""
 
     # Import numpy as np/pyplot as plt are conventions we're trying to
     # somewhat standardize on.  Making them available to users by default
     # will greatly help this. 
     exec ("import numpy\n"
           "import matplotlib\n"
           "from matplotlib import pylab, mlab, pyplot\n"
           "np = numpy\n"
           "plt = pyplot\n"
           ) in user_ns
 
     if import_all:
         exec("from matplotlib.pylab import *\n"
              "from numpy import *\n") in user_ns
 
 
 def pylab_activate(user_ns, gui=None, import_all=True):
     """Activate pylab mode in the user's namespace.
 
     Loads and initializes numpy, matplotlib and friends for interactive use.
 
     Parameters
     ----------
     user_ns : dict
       Namespace where the imports will occur.
 
     gui : optional, string
       A valid gui name following the conventions of the %gui magic.
 
     import_all : optional, boolean
       If true, an 'import *' is done from numpy and pylab.
 
     Returns
     -------
     The actual gui used (if not given as input, it was obtained from matplotlib
     itself, and will be needed next to configure IPython's gui integration.
     """
-
     gui, backend = find_gui_and_backend(gui)
     activate_matplotlib(backend)
-
-    # This must be imported last in the matplotlib series, after
-    # backend/interactivity choices have been made
-    import matplotlib.pylab as pylab
-
-    # XXX For now leave this commented out, but depending on discussions with
-    # mpl-dev, we may be able to allow interactive switching...
-    #import matplotlib.pyplot
-    #matplotlib.pyplot.switch_backend(backend)
-
-    pylab.show._needmain = False
-    # We need to detect at runtime whether show() is called by the user.
-    # For this, we wrap it into a decorator which adds a 'called' flag.
-    pylab.draw_if_interactive = flag_calls(pylab.draw_if_interactive)
-
     import_pylab(user_ns)
 
     print """
 Welcome to pylab, a matplotlib-based Python environment [backend: %s].
 For more information, type 'help(pylab)'.""" % backend
     
     return gui
 
 # We need a little factory function here to create the closure where
 # safe_execfile can live.
 def mpl_runner(safe_execfile):
     """Factory to return a matplotlib-enabled runner for %run.
 
     Parameters
     ----------
     safe_execfile : function
       This must be a function with the same interface as the
       :meth:`safe_execfile` method of IPython.
 
     Returns
     -------
     A function suitable for use as the ``runner`` argument of the %run magic
     function.
     """
     
     def mpl_execfile(fname,*where,**kw):
         """matplotlib-aware wrapper around safe_execfile.
 
         Its interface is identical to that of the :func:`execfile` builtin.
 
         This is ultimately a call to execfile(), but wrapped in safeties to
         properly handle interactive rendering."""
 
         import matplotlib
         import matplotlib.pylab as pylab
 
         #print '*** Matplotlib runner ***' # dbg
         # turn off rendering until end of script
         is_interactive = matplotlib.rcParams['interactive']
         matplotlib.interactive(False)
         safe_execfile(fname,*where,**kw)
         matplotlib.interactive(is_interactive)
         # make rendering call now, if the user tried to do it
         if pylab.draw_if_interactive.called:
             pylab.draw()
             pylab.draw_if_interactive.called = False
 
     return mpl_execfile

IPython/zmq/ipkernel.py

@@ -1,391 +1,453
 #!/usr/bin/env python
 """A simple interactive kernel that talks to a frontend over 0MQ.
 
 Things to do:
 
 * Implement `set_parent` logic. Right before doing exec, the Kernel should
   call set_parent on all the PUB objects with the message about to be executed.
 * Implement random port and security key logic.
 * Implement control messages.
 * Implement event loop and poll version.
 """
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Standard library imports.
 import __builtin__
 import sys
 import time
 import traceback
 
 # System library imports.
 import zmq
 
 # Local imports.
 from IPython.config.configurable import Configurable
 from IPython.lib import pylabtools
 from IPython.utils.traitlets import Instance
 from entry_point import base_launch_kernel, make_argument_parser, make_kernel, \
     start_kernel
 from iostream import OutStream
 from session import Session, Message
 from zmqshell import ZMQInteractiveShell
 
 #-----------------------------------------------------------------------------
 # Main kernel class
 #-----------------------------------------------------------------------------
 
 class Kernel(Configurable):
 
     #---------------------------------------------------------------------------
     # Kernel interface
     #---------------------------------------------------------------------------
 
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC')
     session = Instance(Session)
     reply_socket = Instance('zmq.Socket')
     pub_socket = Instance('zmq.Socket')
     req_socket = Instance('zmq.Socket')
 
     def __init__(self, **kwargs):
         super(Kernel, self).__init__(**kwargs)
 
         # Initialize the InteractiveShell subclass
         self.shell = ZMQInteractiveShell.instance()
         self.shell.displayhook.session = self.session
         self.shell.displayhook.pub_socket = self.pub_socket
 
         # TMP - hack while developing
         self.shell._reply_content = None
 
         # Build dict of handlers for message types
         msg_types = [ 'execute_request', 'complete_request', 
                       'object_info_request', 'prompt_request',
                       'history_request' ]
         self.handlers = {}
         for msg_type in msg_types:
             self.handlers[msg_type] = getattr(self, msg_type)
 
     def do_one_iteration(self):
         try:
             ident = self.reply_socket.recv(zmq.NOBLOCK)
         except zmq.ZMQError, e:
             if e.errno == zmq.EAGAIN:
                 return
             else:
                 raise
         # FIXME: Bug in pyzmq/zmq?
         # assert self.reply_socket.rcvmore(), "Missing message part."
         msg = self.reply_socket.recv_json()
         omsg = Message(msg)
         print>>sys.__stdout__
         print>>sys.__stdout__, omsg
         handler = self.handlers.get(omsg.msg_type, None)
         if handler is None:
             print >> sys.__stderr__, "UNKNOWN MESSAGE TYPE:", omsg
         else:
             handler(ident, omsg)
 
     def start(self):
         """ Start the kernel main loop.
         """
         while True:
             time.sleep(0.05)
             self.do_one_iteration()
 
     #---------------------------------------------------------------------------
     # Kernel request handlers
     #---------------------------------------------------------------------------
 
     def execute_request(self, ident, parent):
         try:
             code = parent[u'content'][u'code']
         except:
             print>>sys.__stderr__, "Got bad msg: "
             print>>sys.__stderr__, Message(parent)
             return
         pyin_msg = self.session.msg(u'pyin',{u'code':code}, parent=parent)
         self.pub_socket.send_json(pyin_msg)
 
         try:
             # Replace raw_input. Note that is not sufficient to replace 
             # raw_input in the user namespace.
             raw_input = lambda prompt='': self._raw_input(prompt, ident, parent)
             __builtin__.raw_input = raw_input
 
             # Set the parent message of the display hook and out streams.
             self.shell.displayhook.set_parent(parent)
             sys.stdout.set_parent(parent)
             sys.stderr.set_parent(parent)
 
             # FIXME: runlines calls the exception handler itself.  We should
             # clean this up.
             self.shell._reply_content = None
             self.shell.runlines(code)
         except:
             # FIXME: this code right now isn't being used yet by default,
             # because the runlines() call above directly fires off exception
             # reporting.  This code, therefore, is only active in the scenario
             # where runlines itself has an unhandled exception.  We need to
             # uniformize this, for all exception construction to come from a
             # single location in the codbase.
             etype, evalue, tb = sys.exc_info()
             tb_list = traceback.format_exception(etype, evalue, tb)
             reply_content = self.shell._showtraceback(etype, evalue, tb_list)
         else:
             payload = self.shell.payload_manager.read_payload()
             # Be agressive about clearing the payload because we don't want
             # it to sit in memory until the next execute_request comes in.
             self.shell.payload_manager.clear_payload()
             reply_content = { 'status' : 'ok', 'payload' : payload }
 
         # Compute the prompt information
         prompt_number = self.shell.displayhook.prompt_count
         reply_content['prompt_number'] = prompt_number        
         prompt_string = self.shell.displayhook.prompt1.peek_next_prompt()
         next_prompt = {'prompt_string' : prompt_string,
                        'prompt_number' : prompt_number+1,
                        'input_sep'     : self.shell.displayhook.input_sep}
         reply_content['next_prompt'] = next_prompt
 
         # TMP - fish exception info out of shell, possibly left there by
         # runlines
         if self.shell._reply_content is not None:
             reply_content.update(self.shell._reply_content)
 
         # Flush output before sending the reply.
         sys.stderr.flush()
         sys.stdout.flush()
 
         # Send the reply.
         reply_msg = self.session.msg(u'execute_reply', reply_content, parent)
         print>>sys.__stdout__, Message(reply_msg)
         self.reply_socket.send(ident, zmq.SNDMORE)
         self.reply_socket.send_json(reply_msg)
         if reply_msg['content']['status'] == u'error':
             self._abort_queue()
 
     def complete_request(self, ident, parent):
         matches = {'matches' : self._complete(parent),
                    'status' : 'ok'}
         completion_msg = self.session.send(self.reply_socket, 'complete_reply',
                                            matches, parent, ident)
         print >> sys.__stdout__, completion_msg
 
     def object_info_request(self, ident, parent):
         context = parent['content']['oname'].split('.')
         object_info = self._object_info(context)
         msg = self.session.send(self.reply_socket, 'object_info_reply',
                                 object_info, parent, ident)
         print >> sys.__stdout__, msg
 
     def prompt_request(self, ident, parent):
         prompt_number = self.shell.displayhook.prompt_count
         prompt_string = self.shell.displayhook.prompt1.peek_next_prompt()
         content = {'prompt_string' : prompt_string,
                    'prompt_number' : prompt_number+1,
                    'input_sep'     : self.shell.displayhook.input_sep}
         msg = self.session.send(self.reply_socket, 'prompt_reply',
                                 content, parent, ident)
         print >> sys.__stdout__, msg
 
     def history_request(self, ident, parent):
         output = parent['content']['output']
         index = parent['content']['index']
         raw = parent['content']['raw']
         hist = self.shell.get_history(index=index, raw=raw, output=output)
         content = {'history' : hist}
         msg = self.session.send(self.reply_socket, 'history_reply',
                                 content, parent, ident)
         print >> sys.__stdout__, msg
         
     #---------------------------------------------------------------------------
     # Protected interface
     #---------------------------------------------------------------------------
 
     def _abort_queue(self):
         while True:
             try:
                 ident = self.reply_socket.recv(zmq.NOBLOCK)
             except zmq.ZMQError, e:
                 if e.errno == zmq.EAGAIN:
                     break
             else:
                 assert self.reply_socket.rcvmore(), "Unexpected missing message part."
                 msg = self.reply_socket.recv_json()
             print>>sys.__stdout__, "Aborting:"
             print>>sys.__stdout__, Message(msg)
             msg_type = msg['msg_type']
             reply_type = msg_type.split('_')[0] + '_reply'
             reply_msg = self.session.msg(reply_type, {'status' : 'aborted'}, msg)
             print>>sys.__stdout__, Message(reply_msg)
             self.reply_socket.send(ident,zmq.SNDMORE)
             self.reply_socket.send_json(reply_msg)
             # We need to wait a bit for requests to come in. This can probably
             # be set shorter for true asynchronous clients.
             time.sleep(0.1)
 
     def _raw_input(self, prompt, ident, parent):
         # Flush output before making the request.
         sys.stderr.flush()
         sys.stdout.flush()
 
         # Send the input request.
         content = dict(prompt=prompt)
         msg = self.session.msg(u'input_request', content, parent)
         self.req_socket.send_json(msg)
 
         # Await a response.
         reply = self.req_socket.recv_json()
         try:
             value = reply['content']['value']
         except:
             print>>sys.__stderr__, "Got bad raw_input reply: "
             print>>sys.__stderr__, Message(parent)
             value = ''
         return value
     
     def _complete(self, msg):
         #from IPython.utils.io import rprint  # dbg
         #rprint('\n\n**MSG**\n\n', msg)  # dbg
         #import traceback; rprint(''.join(traceback.format_stack())) # dbg
         c = msg['content']
         try:
             cpos = int(c['cursor_pos'])
         except:
             # If we don't get something that we can convert to an integer, at
             # leasat attempt the completion guessing the cursor is at the end
             # of the text
             cpos = len(c['text'])
         return self.shell.complete(c['text'], c['line'], cpos)
 
     def _object_info(self, context):
         symbol, leftover = self._symbol_from_context(context)
         if symbol is not None and not leftover:
             doc = getattr(symbol, '__doc__', '')
         else:
             doc = ''
         object_info = dict(docstring = doc)
         return object_info
 
     def _symbol_from_context(self, context):
         if not context:
             return None, context
 
         base_symbol_string = context[0]
         symbol = self.shell.user_ns.get(base_symbol_string, None)
         if symbol is None:
             symbol = __builtin__.__dict__.get(base_symbol_string, None)
         if symbol is None:
             return None, context
 
         context = context[1:]
         for i, name in enumerate(context):
             new_symbol = getattr(symbol, name, None)
             if new_symbol is None:
                 return symbol, context[i:]
             else:
                 symbol = new_symbol
 
         return symbol, []
 
 
 class QtKernel(Kernel):
+    """A Kernel subclass with Qt support."""
 
     def start(self):
         """Start a kernel with QtPy4 event loop integration."""
+
         from PyQt4 import QtGui, QtCore
-        self.qapp = app = QtGui.QApplication([])
-        self.qtimer = QtCore.QTimer()
-        self.qtimer.timeout.connect(self.do_one_iteration)
-        self.qtimer.start(50)
-        self.qapp.exec_()
+        self.app = QtGui.QApplication([])
+        self.app.setQuitOnLastWindowClosed (False)
+        self.timer = QtCore.QTimer()
+        self.timer.timeout.connect(self.do_one_iteration)
+        self.timer.start(50)
+        self.app.exec_()
+
+
+class WxKernel(Kernel):
+    """A Kernel subclass with Wx support."""
+
+    def start(self):
+        """Start a kernel with wx event loop support."""
+
+        import wx
+        doi = self.do_one_iteration
+
+        # We have to put the wx.Timer in a wx.Frame for it to fire properly.
+        # We make the Frame hidden when we create it in the main app below.
+        class TimerFrame(wx.Frame):
+            def __init__(self, func):
+                wx.Frame.__init__(self, None, -1)
+                self.timer = wx.Timer(self)
+                self.timer.Start(50)
+                self.Bind(wx.EVT_TIMER, self.on_timer)
+                self.func = func
+            def on_timer(self, event):
+                self.func()
+
+        # We need a custom wx.App to create our Frame subclass that has the
+        # wx.Timer to drive the ZMQ event loop.
+        class IPWxApp(wx.App):
+            def OnInit(self):
+                self.frame = TimerFrame(doi)
+                self.frame.Show(False)
+                return True
+
+        # The redirect=False here makes sure that wx doesn't replace
+        # sys.stdout/stderr with its own classes.
+        self.app = IPWxApp(redirect=False)
+        self.app.MainLoop()
+
+
+class TkKernel(Kernel):
+    """A Kernel subclass with Tk support."""
+
+    def start(self):
+        """Start a Tk enabled event loop."""
+
+        import Tkinter
+        doi = self.do_one_iteration
+
+        # For Tkinter, we create a Tk object and call its withdraw method.
+        class Timer(object):
+            def __init__(self, func):
+                self.app = Tkinter.Tk()
+                self.app.withdraw()
+                self.func = func
+            def on_timer(self):
+                self.func()
+                self.app.after(50, self.on_timer)
+            def start(self):
+                self.on_timer()  # Call it once to get things going.
+                self.app.mainloop()
 
+        self.timer = Timer(doi)
+        self.timer.start()
 
 #-----------------------------------------------------------------------------
 # Kernel main and launch functions
 #-----------------------------------------------------------------------------
 
 def launch_kernel(xrep_port=0, pub_port=0, req_port=0, independent=False,
                   pylab=False):
     """ Launches a localhost kernel, binding to the specified ports.
 
     Parameters
     ----------
     xrep_port : int, optional
         The port to use for XREP channel.
 
     pub_port : int, optional
         The port to use for the SUB channel.
 
     req_port : int, optional
         The port to use for the REQ (raw input) channel.
 
     independent : bool, optional (default False) 
         If set, the kernel process is guaranteed to survive if this process
         dies. If not set, an effort is made to ensure that the kernel is killed
         when this process dies. Note that in this case it is still good practice
         to kill kernels manually before exiting.
 
     pylab : bool or string, optional (default False)
         If not False, the kernel will be launched with pylab enabled. If a
         string is passed, matplotlib will use the specified backend. Otherwise,
         matplotlib's default backend will be used.
 
     Returns
     -------
     A tuple of form:
         (kernel_process, xrep_port, pub_port, req_port)
     where kernel_process is a Popen object and the ports are integers.
     """
     extra_arguments = []
     if pylab:
         extra_arguments.append('--pylab')
         if isinstance(pylab, basestring):
             extra_arguments.append(pylab)
     return base_launch_kernel('from IPython.zmq.ipkernel import main; main()',
                               xrep_port, pub_port, req_port, independent, 
                               extra_arguments)
 
 def main():
     """ The IPython kernel main entry point.
     """
     parser = make_argument_parser()
     parser.add_argument('--pylab', type=str, metavar='GUI', nargs='?', 
                         const='auto', help = \
 "Pre-load matplotlib and numpy for interactive use. If GUI is not \
 given, the GUI backend is matplotlib's, otherwise use one of: \
 ['tk', 'gtk', 'qt', 'wx', 'payload-svg'].")
     namespace = parser.parse_args()
 
     kernel_class = Kernel
 
     _kernel_classes = {
         'qt' : QtKernel,
         'qt4' : QtKernel,
-        'payload-svg':Kernel
+        'payload-svg':Kernel,
+        'wx' : WxKernel,
+        'tk' : TkKernel
     }
     if namespace.pylab:
         if namespace.pylab == 'auto':
             gui, backend = pylabtools.find_gui_and_backend()
         else:
             gui, backend = pylabtools.find_gui_and_backend(namespace.pylab)
-        print gui, backend
         kernel_class = _kernel_classes.get(gui)
         if kernel_class is None:
             raise ValueError('GUI is not supported: %r' % gui)
         pylabtools.activate_matplotlib(backend)
 
-    print>>sys.__stdout__, kernel_class
     kernel = make_kernel(namespace, kernel_class, OutStream)
-    print >>sys.__stdout__, kernel
 
     if namespace.pylab:
         pylabtools.import_pylab(kernel.shell.user_ns)
 
     start_kernel(namespace, kernel)
 
 if __name__ == '__main__':
     main()