populates file_names list with urls that matched the regex match object
    returns the total filesize of all the files matched

def get_local_uri(m, file_names, _):
    """
    populates file_names list with urls that matched the regex match object
    returns the total filesize of all the files matched
    """
    path = m.group(2)
    result = 0
    for root, _, files in os.walk(path):
        for file_name in files:
            absolute_path = os.path.join(root, file_name)
            file_names.append("file:/{}".format(absolute_path))
            result += os.path.getsize(absolute_path)
    return result