How to use the isort.parse.file_contents function in isort

def test_file_contents():
    (
        in_lines,
        out_lines,
        import_index,
        place_imports,
        import_placements,
        as_map,
        imports,
        categorized_comments,
        change_count,
        original_line_count,
        line_separator,
        sections,
        section_comments,
    ) = parse.file_contents(TEST_CONTENTS, config=Config())
    assert "\n".join(in_lines) == TEST_CONTENTS
    assert "import" not in "\n".join(out_lines)
    assert import_index == 1
    assert change_count == -2
    assert original_line_count == len(in_lines)

import_section += line
                if not contains_imports:
                    output_stream.write(import_section)
                else:
                    if first_import_section and not import_section.lstrip(
                        line_separator
                    ).startswith(COMMENT_INDICATORS):
                        import_section = import_section.lstrip(line_separator)
                        first_import_section = False

                    if indent:
                        import_section = line_separator.join(
                            line.lstrip() for line in import_section.split(line_separator)
                        )
                    sorted_import_section = output.sorted_imports(
                        parse.file_contents(import_section, config=config), config, extension
                    )
                    if indent:
                        sorted_import_section = (
                            textwrap.indent(sorted_import_section, indent) + line_separator
                        )

                    output_stream.write(sorted_import_section)

                if indent:
                    output_stream.write(line)
                    indent = ""

                contains_imports = False
                import_section = ""
            else:
                output_stream.write(line)