---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-7-ea1bc187199f> in <module>()
----> 1 plt.hist([[], []], color=["k", "r"])

~/.miniconda/envs/leanheat/lib/python3.5/site-packages/matplotlib/pyplot.py in hist(x, bins, range, density, weights, cumulative, bottom, histtype, align, orientation, rwidth, log, color, label, stacked, normed, hold, data, **kwargs)
   3130                       histtype=histtype, align=align, orientation=orientation,
   3131                       rwidth=rwidth, log=log, color=color, label=label,
-> 3132                       stacked=stacked, normed=normed, data=data, **kwargs)
   3133     finally:
   3134         ax._hold = washold

~/.miniconda/envs/leanheat/lib/python3.5/site-packages/matplotlib/__init__.py in inner(ax, *args, **kwargs)
   1853                         "the Matplotlib list!)" % (label_namer, func.__name__),
   1854                         RuntimeWarning, stacklevel=2)
-> 1855             return func(ax, *args, **kwargs)
   1856 
   1857         inner.__doc__ = _add_data_doc(inner.__doc__,

~/.miniconda/envs/leanheat/lib/python3.5/site-packages/matplotlib/axes/_axes.py in hist(***failed resolving arguments***)
   6502             color = mcolors.to_rgba_array(color)
   6503             if len(color) != nx:
-> 6504                 raise ValueError("color kwarg must have one color per dataset")
   6505 
   6506         # If bins are not specified either explicitly or via range,

ValueError: color kwarg must have one color per dataset