Is there a decode function in libcst to convert a tree to python source code?

Question

I got a piece of output from a sample libcst.parse_module program like:

Module(
    body=[
        SimpleStatementLine(
            body=[
                Assign(
                    targets=[
                        AssignTarget(
                            target=Name(
                                value='hi',
                                lpar=[],
                                rpar=[],
                            ),
                            whitespace_before_equal=SimpleWhitespace(
                                value=' ',
                            ),
                            whitespace_after_equal=SimpleWhitespace(
                                value=' ',
                            ),
                        ),
                    ],
                    value=Integer(
                        value='0',
                        lpar=[],
                        rpar=[],
                    ),
                    semicolon=MaybeSentinel.DEFAULT,
                ),
            ],
            leading_lines=[],
            trailing_whitespace=TrailingWhitespace(
                whitespace=SimpleWhitespace(
                    value='',
                ),
                comment=None,
                newline=Newline(
                    value=None,
                ),
            ),
        ),
    ],
    header=[],
    footer=[],
    encoding='utf-8',
    default_indent='    ',
    default_newline='\n',
    has_trailing_newline=False,
)

I search a lot but still don't know how to decode this cst tree back to python source code. Can anyone help?

I have read this document libcst but there was only the tutorial to encode python source code into cst tree using parse_module. Can't find the way to decode cst tree back to python source code.