Convert XML to its C14N 2.0 serialised form.
If *out* is provided, it must be a file or file-like object that
receives the serialised canonical XML output (text, not bytes) through
its ``.write()`` method. To write to a file, open it in text mode with
encoding "utf-8". If *out* is not provided, this function returns the
output as text string.
Either *xml_data* (an XML string) or *from_file* (a file path or
file-like object) must be provided as input.
The configuration options are the same as for the ``C14NWriterTarget``.