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 unique_name():
    now_time = datetime.datetime.now().strftime("%Y%m%d%H%M%S")
    random_num = random.randint(0, 100)
    if random_num <= 10:
        random_num = str(0) + str(random_num)
    unique_num = str(now_time) + str(random_num)
    return unique_num