Return the identity of the Term that would be constructed from the
        given arguments.

        Identities that compare equal will cause us to return a cached instance
        rather than constructing a new one.  We do this primarily because it
        makes dependency resolution easier.

        This is a classmethod so that it can be called from Term.__new__ to
        determine whether to produce a new instance.

def _static_identity(cls,
                         domain,
                         dtype,
                         missing_value,
                         window_safe,
                         ndim,
                         params):
        """
        Return the identity of the Term that would be constructed from the
        given arguments.

        Identities that compare equal will cause us to return a cached instance
        rather than constructing a new one.  We do this primarily because it
        makes dependency resolution easier.

        This is a classmethod so that it can be called from Term.__new__ to
        determine whether to produce a new instance.
        """
        return (cls, domain, dtype, missing_value, window_safe, ndim, params)