fu.py

from functools import wraps


def juggle(f):
    """
    Suppose we have a binary function
    >>> def add(a, b):
    ...     return a + b

    You could call `it` in following way
    >>> add(1, 2)
    3

    however if we `juggle` the function,
    >>> juggled_add = juggle(add)

    then the juggled function would take single tuple as `args`,
    and apply *args to unwrapped function
    >>> juggled_add((1, 2))
    3

    >>> juggled_add([1, 2])
    Traceback (most recent call last):
        ...
    TypeError: Function `juggle(add)` takes exactly 1 argument, which must be a tuple

    >>> from itertools import product
    >>> from operator import concat
    >>> map(juggle(concat), product([[1], [2]], [[1]]))
    [[1, 1], [2, 1]]
    """

    @wraps(f)
    def wrapper(*args, **kwargs):
        if len(kwargs) == 0 and len(args) == 1 and isinstance(args[0], tuple):
            return f(*args[0])
        else:
            raise TypeError('Function `juggle({})` takes exactly'
                            ' 1 argument, which must be a tuple'.format(f.__name__))
    return wrapper