Getting insecure pickle string with ggplot

Question

I'm trying to use ggplot for Python working inside iPython Notebook, but when running from ggplot import * the following error appears:

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-22-2199c088d178> in <module>()
      2 import numpy as np
      3 import dateutil
----> 4 from ggplot import *

~/ipython-venv/lib/python2.7/site-packages/ggplot/__init__.py in <module>()
     19 __version__ = '0.6.8'
     20 
---> 21 from .qplot import qplot
     22 from .ggplot import ggplot
     23 from .components import aes

~/ipython-venv/lib/python2.7/site-packages/ggplot/qplot.py in <module>()
      3 
      4 import ggplot
----> 5 from .components import aes
      6 from .geoms import geom_point, geom_bar, geom_boxplot, geom_histogram, geom_line
      7 from .geoms.chart_components import xlab as xlabel

~/ipython-venv/lib/python2.7/site-packages/ggplot/components/__init__.py in <module>()
      2                         unicode_literals)
      3 from .aes import aes
----> 4 from . import colors, shapes, size, linetypes, alphas
      5 
      6 

~/ipython-venv/lib/python2.7/site-packages/ggplot/components/colors.py in <module>()
      4 import numpy as np
      5 from matplotlib.colors import rgb2hex
----> 6 from ..utils.color import ColorHCL
      7 from .legend import get_labels
      8 from copy import deepcopy

~/ipython-venv/lib/python2.7/site-packages/ggplot/utils/__init__.py in <module>()
      2                         unicode_literals)
      3 
----> 4 from .ggutils import ggsave, add_ggplotrc_params
      5 from .date_breaks import date_breaks
      6 from .date_format import date_format

~/ipython-venv/lib/python2.7/site-packages/ggplot/utils/ggutils.py in <module>()
      4                         unicode_literals)
      5 
----> 6 import matplotlib.pyplot as plt
      7 import json
      8 import os

~/ipython-venv/lib/python2.7/site-packages/matplotlib/pyplot.py in <module>()
     27 from cycler import cycler
     28 import matplotlib
---> 29 import matplotlib.colorbar
     30 from matplotlib import style
     31 from matplotlib import _pylab_helpers, interactive

~/ipython-venv/lib/python2.7/site-packages/matplotlib/colorbar.py in <module>()
     32 import matplotlib.artist as martist
     33 import matplotlib.cbook as cbook
---> 34 import matplotlib.collections as collections
     35 import matplotlib.colors as colors
     36 import matplotlib.contour as contour

~/ipython-venv/lib/python2.7/site-packages/matplotlib/collections.py in <module>()
     25 import matplotlib.artist as artist
     26 from matplotlib.artist import allow_rasterization
---> 27 import matplotlib.backend_bases as backend_bases
     28 import matplotlib.path as mpath
     29 from matplotlib import _path

~/ipython-venv/lib/python2.7/site-packages/matplotlib/backend_bases.py in <module>()
     60 
     61 import matplotlib.tight_bbox as tight_bbox
---> 62 import matplotlib.textpath as textpath
     63 from matplotlib.path import Path
     64 from matplotlib.cbook import mplDeprecation, warn_deprecated

~/ipython-venv/lib/python2.7/site-packages/matplotlib/textpath.py in <module>()
     13 from matplotlib.path import Path
     14 from matplotlib import rcParams
---> 15 import matplotlib.font_manager as font_manager
     16 from matplotlib.ft2font import FT2Font, KERNING_DEFAULT, LOAD_NO_HINTING
     17 from matplotlib.ft2font import LOAD_TARGET_LIGHT

~/ipython-venv/lib/python2.7/site-packages/matplotlib/font_manager.py in <module>()
   1419                 verbose.report("Using fontManager instance from %s" % _fmcache)
   1420         except:
-> 1421             _rebuild()
   1422     else:
   1423         _rebuild()

~/ipython-venv/lib/python2.7/site-packages/matplotlib/font_manager.py in _rebuild()
   1404     def _rebuild():
   1405         global fontManager
-> 1406         fontManager = FontManager()
   1407         if _fmcache:
   1408             pickle_dump(fontManager, _fmcache)

~/ipython-venv/lib/python2.7/site-packages/matplotlib/font_manager.py in __init__(self, size, weight)
   1042         #  Load TrueType fonts and create font dictionary.
   1043 
-> 1044         self.ttffiles = findSystemFonts(paths) + findSystemFonts()
   1045         self.defaultFamily = {
   1046             'ttf': 'Bitstream Vera Sans',

~/ipython-venv/lib/python2.7/site-packages/matplotlib/font_manager.py in findSystemFonts(fontpaths, fontext)
    322                     fontfiles[f] = 1
    323 
--> 324             for f in get_fontconfig_fonts(fontext):
    325                 fontfiles[f] = 1
    326 

~/ipython-venv/lib/python2.7/site-packages/matplotlib/font_manager.py in get_fontconfig_fonts(fontext)
    274         pipe = subprocess.Popen(['fc-list', '--format=%{file}\\n'],
    275                                 stdout=subprocess.PIPE,
--> 276                                 stderr=subprocess.PIPE)
    277         output = pipe.communicate()[0]
    278     except (OSError, IOError):

/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.pyc in __init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags)
    708                                 p2cread, p2cwrite,
    709                                 c2pread, c2pwrite,
--> 710                                 errread, errwrite)
    711         except Exception:
    712             # Preserve original exception in case os.close raises.

/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.pyc in _execute_child(self, args, executable, preexec_fn, close_fds, cwd, env, universal_newlines, startupinfo, creationflags, shell, to_close, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite)
   1332                     if e.errno != errno.ECHILD:
   1333                         raise
-> 1334                 child_exception = pickle.loads(data)
   1335                 raise child_exception
   1336 

/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.pyc in loads(str)
   1386 def loads(str):
   1387     file = StringIO(str)
-> 1388     return Unpickler(file).load()
   1389 
   1390 # Doctest

/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.pyc in load(self)
    862             while 1:
    863                 key = read(1)
--> 864                 dispatch[key](self)
    865         except _Stop, stopinst:
    866             return stopinst.value

/usr/local/Cellar/python/2.7.11/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.pyc in load_string(self)
    970             if rep.startswith(q):
    971                 if len(rep) < 2 or not rep.endswith(q):
--> 972                     raise ValueError, "insecure string pickle"
    973                 rep = rep[len(q):-len(q)]
    974                 break

ValueError: insecure string pickle

The environment running is on OS-X El Capitan, Python 2.x is installed through HomeBrew, and the following libraries are installed:

(ipython-venv)➜ ~ pip list appnope (0.1.0) backports-abc (0.4) backports.ssl-match-hostname (3.5.0.1) beautifulsoup4 (4.4.1) brewer2mpl (1.4.1) certifi (2015.11.20.1) cycler (0.9.0) decorator (4.0.6) functools32 (3.2.3.post2) ggplot (0.6.8) gnureadline (6.3.3) ipykernel (4.2.2) ipython (4.0.3) ipython-genutils (0.1.0) Jinja2 (2.8) jsonschema (2.5.1) jupyter-client (4.1.1) jupyter-core (4.0.6) MarkupSafe (0.23) matplotlib (1.5.1) mechanize (0.2.5) mistune (0.7.1) nbconvert (4.1.0) nbformat (4.0.1) notebook (4.1.0) numpy (1.10.4) pandas (0.17.1) path.py (8.1.2) patsy (0.4.1) pexpect (4.0.1) pickleshare (0.6) pip (8.0.2) ptyprocess (0.5) Pygments (2.1) pyparsing (2.1.0) python-dateutil (2.4.2) pytz (2015.7) pyzmq (15.2.0) scipy (0.17.0) selenium (2.50.0) setuptools (15.0) simplegeneric (0.8.1) singledispatch (3.4.0.3) six (1.10.0) statsmodels (0.6.1) termcolor (1.1.0) terminado (0.6) tornado (4.3) traitlets (4.1.0)

Answer 1

This has been discussed here: github.com/matplotlib/matplotlib/pull/5640.

It may be a permissions issue - matplotlib shouldn't be building that cache every time

The suggestion there is to delete the contents of ~/.cache/matplotlib and try again.