Remove FunctionChain.__getitem__
This has unintended sideeffects* and is not necessary since the functions
attribute is exposed.
*For example, np.array([chain])
produces an array with each function in
chain as an individual element.
This has unintended sideeffects* and is not necessary since the functions
attribute is exposed.
*For example, np.array([chain])
produces an array with each function in
chain as an individual element.