def apply(self, doc):
if not isinstance(doc, Document):<EOL><INDENT>raise TypeError(<EOL>"<STR_LIT>"<EOL>)<EOL><DEDENT>for section in doc.sections:<EOL><INDENT>yield TemporarySectionMention(section)<EOL><DEDENT>
Generate MentionSections from a Document by parsing all of its Sections.

:param doc: The ``Document`` to parse.
:type doc: ``Document``
:raises TypeError: If the input doc is not of type ``Document``.