def remove(self, elem):
        """Remove a requirement.

        :param elem: a string or :class:`Requirement` instance.
        """
        if isinstance(elem, text_type):
            for requirement in self:
                if requirement.package == elem:
                    return super(Requirements, self).remove(requirement)
        return super(Requirements, self).remove(elem)
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()