t
is :data:`None` to ignore file-system exceptions.

*follow_links* (:class:`bool` or :data:`None`) optionally is whether to walk
symbolic links that resolve to directories. Default is :data:`None` for
:data:`True`.

*negate* (:class:`bool` or :data:`None`) is whether to negate the match
results of the patterns. If :data:`True`, a pattern matching a file will
exclude the file rather than include it. Default is :data:`None` for
:data:`False`.

Returns the matched files (:class:`~collections.abc.Iterator` of
:class:`.TreeEntry`).
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