import re


def any_char_matches(substring: str, mainString: str):
    """Scans the string for any matches a certain pattern.

    Parameters
    ----------
    substring : str
        The string that is used to find matches from `mainString`.

    mainString : str
        The `mainstring` which contains the original string.

    Returns
    -------
    is_matching : bool
        Returns `True` if the `substring` matches with the `mainSting` else `False`.
    """
    is_matching = bool(re.search(substring, mainString))

    return is_matching