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 anypats(self):
        """None of .always(), .isexact(), and .prefix() is true --
        optimizations will be difficult."""
        return not self.always() and not self.isexact() and not self.prefix()