def loads(self, requirements_text):
        lines = re.findall(Requirement.spec_regex,
                           requirements_text,
                           re.MULTILINE)
        for line in lines:
            self.add(Requirement(line[0], "".join(line[1:])))
def _read_flow(self, file_name):
        return _read_16bits_png_with_flow_and_valid_mask(file_name)