from typing import List


def enforce_str(scope: List) -> str:
    """
    Converts a list of scopes to a space separated string.

    Note:
        If a string is passed to this method it will simply return an
        empty string back. Use :py:func:`enforce_list` to convert
        strings to scope lists.
    Args:
        scope: An iterable or string that contains a list of scope.
    Returns:
        A string of scopes seperated by spaces.
    Raises:
        TypeError: The ``scope`` value passed is not of the proper type.
    """
    if isinstance(scope, (set, tuple, list)):
        return " ".join([str(s) for s in scope])

    return ""