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 __get_linearForce_title_keys(lf):
    if 'force_r' in lf:
        return ['Force r', 'Force z'], ['force_r', 'force_z']
    return ['Force x', 'Force y'], ['force_x', 'force_y']