Backport PR #2169: ipdb: pdef, pdoc, pinfo magics all broken ``` In[1]: dg.meshes.square.qmesh(2) ... IndexError: index (48) out of range (0<=index<47) in dimension 0 In [2]: debug ... ipdb> pinfo jx ... /usr/lib/python2.7/dist-packages/IPython/core/debugger.pyc in do_pinfo(self, arg) 490 namespaces = [('Locals', self.curframe.f_locals), 491 ('Globals', self.curframe.f_globals)] --> 492 self.shell.magic_pinfo("pinfo %s" % arg, namespaces=namespaces) 493 494 def checkline(self, filename, lineno): AttributeError: 'TerminalInteractiveShell' object has no attribute 'magic_pinfo' ```