def strtype(string):
    """ Check string type

    Arguments:
        string: String to check

    Returns:
        Returns one of the following results
        * DIGIT: String is digit [0-9]
        * ALPHA: String is alpha [a-zA-Z]
        * STRING: If no other match is found, it is assumed to be a STRING type
    """
    if str.isdigit(string):
        return 'DIGIT'
    if str.isalpha(string):
        return 'ALPHA'
    return 'STRING'
