{ "metadata": { "gist_id": "5241793", "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Using dill to pickle anything" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "IPython.parallel doesn't do much in the way of serialization.\n", "It has custom zero-copy handling of numpy arrays,\n", "but other than that, it doesn't do anything other than the bare minimum to make basic interactively defined functions and classes sendable.\n", "\n", "There are a few projects that extend pickle to make just about anything sendable, and one of these is [dill](http://www.cacr.caltech.edu/~mmckerns/dill).\n", "\n", "To install dill:\n", " \n", " pip install dill" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "First, as always, we create a task function, this time with a closure" ] }, { "cell_type": "code", "collapsed": false, "input": [ "def make_closure(a):\n", " \"\"\"make a function with a closure, and return it\"\"\"\n", " def has_closure(b):\n", " return a * b\n", " return has_closure" ], "language": "python", "metadata": {}, "outputs": [], "prompt_number": 1 }, { "cell_type": "code", "collapsed": false, "input": [ "closed = make_closure(5)" ], "language": "python", "metadata": {}, "outputs": [], "prompt_number": 2 }, { "cell_type": "code", "collapsed": false, "input": [ "closed(2)" ], "language": "python", "metadata": {}, "outputs": [ { "metadata": {}, "output_type": "pyout", "prompt_number": 3, "text": [ "10" ] } ], "prompt_number": 3 }, { "cell_type": "code", "collapsed": false, "input": [ "import pickle" ], "language": "python", "metadata": {}, "outputs": [], "prompt_number": 4 }, { "cell_type": "markdown", "metadata": {}, "source": [ "Without help, pickle can't deal with closures" ] }, { "cell_type": "code", "collapsed": false, "input": [ "pickle.dumps(closed)" ], "language": "python", "metadata": {}, "outputs": [ { "ename": "PicklingError", "evalue": "Can't pickle : it's not found as __main__.has_closure", "output_type": "pyerr", "traceback": [ "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m\n\u001b[1;31mPicklingError\u001b[0m Traceback (most recent call last)", "\u001b[1;32m\u001b[0m in \u001b[0;36m\u001b[1;34m()\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mpickle\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mdumps\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mclosed\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m", "\u001b[1;32m/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.pyc\u001b[0m in \u001b[0;36mdumps\u001b[1;34m(obj, protocol)\u001b[0m\n\u001b[0;32m 1372\u001b[0m \u001b[1;32mdef\u001b[0m \u001b[0mdumps\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mobj\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mprotocol\u001b[0m\u001b[1;33m=\u001b[0m\u001b[0mNone\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 1373\u001b[0m \u001b[0mfile\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mStringIO\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m-> 1374\u001b[1;33m \u001b[0mPickler\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mfile\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mprotocol\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mdump\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mobj\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m 1375\u001b[0m \u001b[1;32mreturn\u001b[0m \u001b[0mfile\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mgetvalue\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 1376\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n", "\u001b[1;32m/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.pyc\u001b[0m in \u001b[0;36mdump\u001b[1;34m(self, obj)\u001b[0m\n\u001b[0;32m 222\u001b[0m \u001b[1;32mif\u001b[0m \u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mproto\u001b[0m \u001b[1;33m>=\u001b[0m \u001b[1;36m2\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 223\u001b[0m \u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mwrite\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mPROTO\u001b[0m \u001b[1;33m+\u001b[0m \u001b[0mchr\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mproto\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m--> 224\u001b[1;33m \u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0msave\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mobj\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m 225\u001b[0m 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self\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m 287\u001b[0m \u001b[1;32mreturn\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 288\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n", "\u001b[1;32m/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.pyc\u001b[0m in \u001b[0;36msave_global\u001b[1;34m(self, obj, name, pack)\u001b[0m\n\u001b[0;32m 746\u001b[0m raise PicklingError(\n\u001b[0;32m 747\u001b[0m \u001b[1;34m\"Can't pickle %r: it's not found as %s.%s\"\u001b[0m \u001b[1;33m%\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m--> 748\u001b[1;33m (obj, module, name))\n\u001b[0m\u001b[0;32m 749\u001b[0m \u001b[1;32melse\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 750\u001b[0m \u001b[1;32mif\u001b[0m \u001b[0mklass\u001b[0m \u001b[1;32mis\u001b[0m \u001b[1;32mnot\u001b[0m \u001b[0mobj\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n", "\u001b[1;31mPicklingError\u001b[0m: Can't pickle : it's not found as __main__.has_closure" ] } ], "prompt_number": 5 }, { "cell_type": "markdown", "metadata": {}, "source": [ "But after we import dill, magic happens" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import dill" ], "language": "python", "metadata": {}, "outputs": [], "prompt_number": 6 }, { "cell_type": "code", "collapsed": false, "input": [ "pickle.dumps(closed)[:64] + '...'" ], "language": "python", "metadata": {}, "outputs": [ { "metadata": {}, "output_type": "pyout", "prompt_number": 7, "text": [ "\"cdill.dill\\n_load_type\\np0\\n(S'FunctionType'\\np1\\ntp2\\nRp3\\n(cdill.dill...\"" ] } ], "prompt_number": 7 }, { "cell_type": "markdown", "metadata": {}, "source": [ "So from now on, pretty much everything is pickleable." ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Now use this in IPython.parallel" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "As usual, we start by creating our Client and View" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from IPython import parallel\n", "rc = parallel.Client()\n", "view = rc.load_balanced_view()" ], "language": "python", "metadata": {}, "outputs": [], "prompt_number": 8 }, { "cell_type": "markdown", "metadata": {}, "source": [ "Now let's try sending our function with a closure:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "view.apply_sync(closed, 3)" ], "language": "python", "metadata": {}, "outputs": [ { "ename": "ValueError", "evalue": "Sorry, cannot pickle code objects with closures", "output_type": "pyerr", "traceback": [ "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m\n\u001b[1;31mValueError\u001b[0m Traceback (most recent call last)", "\u001b[1;32m\u001b[0m in \u001b[0;36m\u001b[1;34m()\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mview\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mapply_sync\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mclosed\u001b[0m\u001b[1;33m,\u001b[0m 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"\u001b[1;32m/Users/minrk/dev/ip/mine/IPython/parallel/client/view.pyc\u001b[0m in \u001b[0;36msync_results\u001b[1;34m(f, self, *args, **kwargs)\u001b[0m\n\u001b[0;32m 64\u001b[0m \u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0m_in_sync_results\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mTrue\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 65\u001b[0m \u001b[1;32mtry\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m---> 66\u001b[1;33m \u001b[0mret\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mf\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mself\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;33m*\u001b[0m\u001b[0margs\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;33m**\u001b[0m\u001b[0mkwargs\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m 67\u001b[0m \u001b[1;32mfinally\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 68\u001b[0m \u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0m_in_sync_results\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mFalse\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n", "\u001b[1;32m/Users/minrk/dev/ip/mine/IPython/parallel/client/view.pyc\u001b[0m in \u001b[0;36m_really_apply\u001b[1;34m(self, f, args, kwargs, block, track, after, follow, timeout, targets, retries)\u001b[0m\n", "\u001b[1;32m/Users/minrk/dev/ip/mine/IPython/parallel/client/view.pyc\u001b[0m in \u001b[0;36msave_ids\u001b[1;34m(f, self, *args, **kwargs)\u001b[0m\n\u001b[0;32m 49\u001b[0m \u001b[0mn_previous\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mlen\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mclient\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mhistory\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 50\u001b[0m \u001b[1;32mtry\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m---> 51\u001b[1;33m \u001b[0mret\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mf\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mself\u001b[0m\u001b[1;33m,\u001b[0m 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track=track,\n\u001b[1;32m-> 1055\u001b[1;33m metadata=metadata)\n\u001b[0m\u001b[0;32m 1056\u001b[0m \u001b[0mtracker\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mNone\u001b[0m \u001b[1;32mif\u001b[0m \u001b[0mtrack\u001b[0m \u001b[1;32mis\u001b[0m \u001b[0mFalse\u001b[0m \u001b[1;32melse\u001b[0m \u001b[0mmsg\u001b[0m\u001b[1;33m[\u001b[0m\u001b[1;34m'tracker'\u001b[0m\u001b[1;33m]\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 1057\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n", "\u001b[1;32m/Users/minrk/dev/ip/mine/IPython/parallel/client/client.pyc\u001b[0m in \u001b[0;36msend_apply_request\u001b[1;34m(self, socket, f, args, kwargs, metadata, track, ident)\u001b[0m\n\u001b[0;32m 1252\u001b[0m bufs = serialize.pack_apply_message(f, args, kwargs,\n\u001b[0;32m 1253\u001b[0m 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\u001b[1;32mor\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_cellvars\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m---> 38\u001b[1;33m \u001b[1;32mraise\u001b[0m \u001b[0mValueError\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m\"Sorry, cannot pickle code objects with closures\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m 39\u001b[0m args = [co.co_argcount, co.co_nlocals, co.co_stacksize,\n\u001b[0;32m 40\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_flags\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_code\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_consts\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_names\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n", "\u001b[1;31mValueError\u001b[0m: Sorry, cannot pickle code objects with closures" ] } ], "prompt_number": 9 }, { "cell_type": "markdown", "metadata": {}, "source": [ "Oops, no dice. For IPython to work with dill,\n", "there are one or two more steps. IPython will do these for you if you call `pickleutil.use_dill`:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from IPython.utils import pickleutil\n", "pickleutil.use_dill()" ], "language": "python", "metadata": {}, "outputs": [], "prompt_number": 10 }, { "cell_type": "markdown", "metadata": {}, "source": [ "Now let's try again" ] }, { "cell_type": "code", "collapsed": false, "input": [ "view.apply_sync(closed, 3)" ], "language": "python", "metadata": {}, "outputs": [ { "metadata": {}, "output_type": "pyout", "prompt_number": 11, "text": [ "15" ] } ], "prompt_number": 11 }, { "cell_type": "markdown", "metadata": {}, "source": [ "Yay! Now we can use dill to allow IPython.parallel to send anything.\n", "\n", "And that's it! We can send closures and other previously non-pickleables to our engines.\n", "\n", "But wait, there's more!" ] }, { "cell_type": "code", "collapsed": false, "input": [ "view.apply_sync(make_closure, 2)" ], "language": "python", "metadata": {}, "outputs": [ { "ename": "RemoteError", "evalue": "ValueError(Sorry, cannot pickle code objects with closures)", "output_type": "pyerr", "traceback": [ "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m", "\u001b[1;31mValueError\u001b[0m Traceback (most recent call last)\u001b[1;32m/Users/minrk/dev/ip/mine/IPython/kernel/zmq/serialize.pyc\u001b[0m in \u001b[0;36mserialize_object\u001b[1;34m(obj, buffer_threshold, item_threshold)\u001b[0m", "\u001b[0;32m 100\u001b[0m \u001b[0mbuffers\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mextend\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0m_extract_buffers\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mcobj\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mbuffer_threshold\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m", "\u001b[0;32m 101\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m", "\u001b[1;32m--> 102\u001b[1;33m \u001b[0mbuffers\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0minsert\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m0\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mpickle\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mdumps\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mcobj\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;33m-\u001b[0m\u001b[1;36m1\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m", "\u001b[0m\u001b[0;32m 103\u001b[0m \u001b[1;32mreturn\u001b[0m \u001b[0mbuffers\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m", "\u001b[0;32m 104\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m", "\u001b[1;32m/Users/minrk/dev/ip/mine/IPython/utils/codeutil.pyc\u001b[0m in \u001b[0;36mreduce_code\u001b[1;34m(co)\u001b[0m", "\u001b[0;32m 36\u001b[0m \u001b[1;32mdef\u001b[0m \u001b[0mreduce_code\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mco\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m", "\u001b[0;32m 37\u001b[0m \u001b[1;32mif\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_freevars\u001b[0m \u001b[1;32mor\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_cellvars\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m", "\u001b[1;32m---> 38\u001b[1;33m \u001b[1;32mraise\u001b[0m \u001b[0mValueError\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;34m\"Sorry, cannot pickle code objects with closures\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m", "\u001b[0m\u001b[0;32m 39\u001b[0m args = [co.co_argcount, co.co_nlocals, co.co_stacksize,", "\u001b[0;32m 40\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_flags\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_code\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_consts\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mco\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mco_names\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m", "\u001b[1;31mValueError\u001b[0m: Sorry, cannot pickle code objects with closures" ] } ], "prompt_number": 12 }, { "cell_type": "markdown", "metadata": {}, "source": [ "If we want dill support for objects coming *from* the engines,\n", "then we need to call `use_dill()` there as well.\n", "\n", "`DirectView` objects have a method to call `use_dill` locally and on every engine:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "rc[:].use_dill()" ], "language": "python", "metadata": {}, "outputs": [ { "metadata": {}, "output_type": "pyout", "prompt_number": 13, "text": [ "" ] } ], "prompt_number": 13 }, { "cell_type": "markdown", "metadata": {}, "source": [ "This is equivalent to\n", "\n", "```python\n", "from IPython.utils.pickleutil import use_dill\n", "use_dill()\n", "rc[:].apply(use_dill)\n", "```" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "Let's give it a try now:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "remote_closure = view.apply_sync(make_closure, 4)\n", "remote_closure(5)" ], "language": "python", "metadata": {}, "outputs": [ { "metadata": {}, "output_type": "pyout", "prompt_number": 14, "text": [ "20" ] } ], "prompt_number": 14 }, { "cell_type": "markdown", "metadata": {}, "source": [ "At this point, we can send/recv all kinds of stuff" ] }, { "cell_type": "code", "collapsed": false, "input": [ "def outer(a):\n", " def inner(b):\n", " def inner_again(c):\n", " return c * b * a\n", " return inner_again\n", " return inner" ], "language": "python", "metadata": {}, "outputs": [], "prompt_number": 15 }, { "cell_type": "markdown", "metadata": {}, "source": [ "So outer returns a function with a closure, which returns a function with a closure.\n", "\n", "Now, we can resolve the first closure on the engine, the second here, and the third on a different engine,\n", "after passing through a lambda we define here and call there, just for good measure." ] }, { "cell_type": "code", "collapsed": false, "input": [ "view.apply_sync(lambda f: f(3),view.apply_sync(outer, 1)(2))" ], "language": "python", "metadata": {}, "outputs": [ { "metadata": {}, "output_type": "pyout", "prompt_number": 16, "text": [ "6" ] } ], "prompt_number": 16 } ], "metadata": {} } ] }