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 open_pager(self):
        "Open the selected item with the system's pager"
        data = self.get_selected_item()
        if data['type'] == 'Submission':
            text = '\n\n'.join((data['permalink'], data['text']))
            self.term.open_pager(text)
        elif data['type'] == 'Comment':
            text = '\n\n'.join((data['permalink'], data['body']))
            self.term.open_pager(text)
        else:
            self.term.flash()