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(self, force_drop=False, *args, **kwargs):
        """
        Deletes this row. Drops the tenant's schema if the attribute
        auto_drop_schema set to True.
        """
        self._drop_schema(force_drop)
        super().delete(*args, **kwargs)