Monkeypatching `rootpy.BaseFunction.__getitem__()`

rootpy_patches.py

# from rootpy import *
from rootpy.plotting.func import BaseFunction


def getitem_patched(self, value):
    # using `str` instead of `basestring` with py3
    # use six.string_types for py2 compatibility
    if isinstance(value, str):
        idx = self.GetParNumber(value)
    elif isinstance(value, int):
        idx = value
    else:
        raise ValueError('Function index must be a integer or a string')
    return BaseFunction.ParProxy(self, idx)


BaseFunction.__getitem__ = getitem_patched