def interceptable_sender(func, key=None):
    """Get the signal sender to intercept a function call.

    :param func: The function that should be intercepted
    :param key: An optional key in case using just the function
                name would be too generic (e.g. most utils)
    """
    name = '{}.{}'.format(func.__module__, func.__name__)
    return '{}::{}'.format(name, key) if key else name