How to use the unidiff.constants.RE_TARGET_FILENAME.match function in unidiff

def parse_unidiff(diff):
    """Unified diff parser, takes a file-like object as argument."""
    ret = PatchSet()
    current_patch = None

    for line in diff:
        # check for source file header
        check_source = RE_SOURCE_FILENAME.match(line)
        if check_source:
            source_file = check_source.group('filename')
            source_timestamp = check_source.group('timestamp')
            current_patch = None
            continue

        # check for target file header
        check_target = RE_TARGET_FILENAME.match(line)
        if check_target:
            target_file = check_target.group('filename')
            target_timestamp = check_target.group('timestamp')
            current_patch = PatchedFile(source_file, target_file,
                                        source_timestamp, target_timestamp)
            ret.append(current_patch)
            continue

        # check for hunk header
        re_hunk_header = RE_HUNK_HEADER.match(line)
        if re_hunk_header:
            hunk_info = re_hunk_header.groups()
            hunk = _parse_hunk(diff, *hunk_info)
            current_patch.append(hunk)
    return ret

continue

            # check for source file header
            is_source_filename = RE_SOURCE_FILENAME.match(line)
            if is_source_filename:
                source_file = is_source_filename.group('filename')
                source_timestamp = is_source_filename.group('timestamp')
                # reset current file, unless we are processing a rename
                # (in that case, source files should match)
                if current_file is not None and not (current_file.is_rename and
                        current_file.source_file == source_file):
                    current_file = None
                continue

            # check for target file header
            is_target_filename = RE_TARGET_FILENAME.match(line)
            if is_target_filename:
                if current_file is not None and not current_file.is_rename:
                    raise UnidiffParseError('Target without source: %s' % line)
                target_file = is_target_filename.group('filename')
                target_timestamp = is_target_filename.group('timestamp')
                if current_file is None:
                    # add current file to PatchSet
                    current_file = PatchedFile(
                        patch_info, source_file, target_file,
                        source_timestamp, target_timestamp)
                    self.append(current_file)
                    patch_info = None
                continue

            # check for hunk header
            is_hunk_header = RE_HUNK_HEADER.match(line)