chain.py

from functools import partial

def chain(*fns, args=None):
    '''Pass arguments through a series of functions
    
    Parameters
    ----------
    *fns : list of functions
        A list of functions to run consecutively
    args : object or tuple, optional
        An argument that will be passed to the first function
        
    Returns
    -------
    The result of the final function, or a partial function that
    takes any number of arguments if the `args` was not set.
    
    Example
    -------
    >>> chain(str.upper, iter, lambda s: ' '.join(s), args='testing')
    'T E S T I N G'
    '''
        
    if args is None:
        return partial(lambda *args: chain(*fns, args=args))
    for fn in fns:
        if not isinstance(args, tuple):
            args = (args,)
        args = fn(*args)
    return args