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 setup_run_environment(self, env):
        bashrc = self.prefix.etc.bashrc
        try:
            env.extend(EnvironmentModifications.from_sourcing_file(
                bashrc, clean=True
            ))
        except Exception as e:
            msg = 'unexpected error when sourcing OpenFOAM bashrc [{0}]'
            tty.warn(msg.format(str(e)))