How to use the pathspec.compat.unicode function in pathspec

def _is_iterable(value):
	"""
	Check whether the value is an iterable (excludes strings).

	*value* is the value to check,

	Returns whether *value* is a iterable (:class:`bool`).
	"""
	return isinstance(value, Iterable) and not isinstance(value, (unicode, bytes))

def pattern_to_regex(cls, pattern):
		"""
		Convert the pattern into a regular expression.

		*pattern* (:class:`unicode` or :class:`bytes`) is the pattern to
		convert into a regular expression.

		Returns the uncompiled regular expression (:class:`unicode`, :class:`bytes`,
		or :data:`None`), and whether matched files should be included
		(:data:`True`), excluded (:data:`False`), or if it is a
		null-operation (:data:`None`).
		"""
		if isinstance(pattern, unicode):
			return_type = unicode
		elif isinstance(pattern, bytes):
			return_type = bytes
			pattern = pattern.decode(_BYTES_ENCODING)
		else:
			raise TypeError("pattern:{!r} is not a unicode or byte string.".format(pattern))

		pattern = pattern.strip()

		if pattern.startswith('#'):
			# A pattern starting with a hash ('#') serves as a comment
			# (neither includes nor excludes files). Escape the hash with a
			# back-slash to match a literal hash (i.e., '\#').
			regex = None
			include = None

unless *pattern* is a precompiled regular expression (:class:`re.RegexObject`)
		in which case it is whether matched files should be included
		(:data:`True`), excluded (:data:`False`), or is a null operation
		(:data:`None`).

			.. NOTE:: Subclasses do not need to support the *include*
			   parameter.
		"""

		self.regex = None
		"""
		*regex* (:class:`re.RegexObject`) is the regular expression for the
		pattern.
		"""

		if isinstance(pattern, (unicode, bytes)):
			assert include is None, "include:{!r} must be null when pattern:{!r} is a string.".format(include, pattern)
			regex, include = self.pattern_to_regex(pattern)
			# NOTE: Make sure to allow a null regular expression to be
			# returned for a null-operation.
			if include is not None:
				regex = re.compile(regex)

		elif pattern is not None and hasattr(pattern, 'match'):
			# Assume pattern is a precompiled regular expression.
			# - NOTE: Used specified *include*.
			regex = pattern

		elif pattern is None:
			# NOTE: Make sure to allow a null pattern to be passed for a
			# null-operation.
			assert include is None, "include:{!r} must be null when pattern:{!r} is null.".format(include, pattern)