def __init__(self, package, version):
        """Construct a new requirement.

        :param package: the package name.
        :param version: a semver compatible version specification.
        """
        self.package = package
        self.version = version
        if self.version and not re.match(r"[<=>~]", version[:2]):
            self.version = "=={}".format(self.version)
def delete_lines(self, min_row, max_row):
        if min_row == -1:
            self.current_label.fuzz_values = self.current_label.fuzz_values[:-1]
        else:
            self.current_label.fuzz_values = self.current_label.fuzz_values[:min_row] + self.current_label.fuzz_values[
                                                                                        max_row + 1:]

        _ = self.current_label  # if user deleted all, this will restore a fuzz value

        self.fuzz_table_model.update()