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 values(cls, dataset, dim, expanded=True, flat=True, compute=True,
               keep_index=False):
        dim = dataset.get_dimension(dim, strict=True)
        data = dataset.data[dim.name]
        if not expanded:
            data = data.unique()
            return data.values_host if compute else data.values
        elif keep_index:
            return data
        elif compute:
            return data.values_host
        try:
            return data.values
        except Exception:
            return data.values_host