def coerce(cls, string):
        """Create a :class:`Requirement` object from a given package spec."""
        match = re.match(cls.spec_regex, string)
        if not match:
            raise InvalidRequirementSpecError("could not parse requirement")
        package = match.group(1)
        if all(match.group(2, 3)):
            version = "".join(match.group(2, 3))
        else:
            version = None
        return cls(package, version)
def __add_fuzzing_boundaries(self):
        lower_bound = -1
        if self.ui.spinBoxLowerBound.isEnabled():
            lower_bound = self.ui.spinBoxLowerBound.value()

        upper_bound = -1
        if self.ui.spinBoxUpperBound.isEnabled():
            upper_bound = self.ui.spinBoxUpperBound.value()

        num_vals = self.ui.spinBoxBoundaryNumber.value()
        self.fuzz_table_model.add_boundaries(lower_bound, upper_bound, num_vals)