def METHOD_NAME(self, name):
    for basis in self.bases:
        # This is hacky...
        if isinstance(basis.coords, Coordinate):
            if name == basis.coords.name:
                return basis.coords
        else:
            for basis_coord in basis.coords.coords:
                if name == basis_coord.name:
                    return basis_coord
    raise ValueError("Coordinate name not in domain")