Checks if the given input is an intrinsic function dictionary. Intrinsic function is a dictionary with single
    key that is the name of the intrinsics.

    :param input: Input value to check if it is an intrinsic
    :return: True, if yes

def is_instrinsic(input):
    """
    Checks if the given input is an intrinsic function dictionary. Intrinsic function is a dictionary with single
    key that is the name of the intrinsics.

    :param input: Input value to check if it is an intrinsic
    :return: True, if yes
    """

    if input is not None \
            and isinstance(input, dict) \
            and len(input) == 1:

        key = list(input.keys())[0]
        return key == "Ref" or key == "Condition" or key.startswith("Fn::")

    return False