:meth:`.WNetworkClientProto.change_directory` method implementation

def change_directory(self, path, *args, **kwargs):
		""" :meth:`.WNetworkClientProto.change_directory` method implementation
		"""
		previous_path = self.session_path()
		self.session_path(path)
		if os.path.isdir(self.full_path()) is False:
			self.session_path(previous_path)
			raise ValueError('Unable to change directory. It does not exist or is not a directory')