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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def tobytes(
 self,
 root=None,
 encoding='UTF-8',
 doctype=None,
 canonicalized=True,
 xml_declaration=True,
 pretty_print=True,
 with_comments=True,
 ):

 """return the content of the XML document as a byte string suitable for writing"""

        if root is None:
            root = self.root
        if canonicalized == True:
            return self.canonicalized_bytes(root)
        else:
            return etree.tostring(
                root,
                encoding=encoding or self.info.encoding,
                doctype=doctype or self.info.doctype,
                xml_declaration=xml_declaration,
                pretty_print=pretty_print,
                with_comments=with_comments,
            )