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 draw_error(layout, message):
        lines = message.split("\n")
        box = layout.box()
        sub = box.row()
        sub.label(lines[0])
        sub.label(icon='ERROR')
        for l in lines[1:]:
            box.label(l)