def METHOD_NAME(self, *args, **kwargs):
    """Assemble the bilinear form into a sparse matrix.
    Parameters
    ----------
    ubasis
        The :class:`~skfem.assembly.Basis` for ``u``.
    vbasis
        Optionally, specify a different :class:`~skfem.assembly.Basis`
        for ``v``.
    **kwargs
        Any additional keyword arguments are appended to ``w``.
    """
    assert self.form is not None
    logger.info("Assembling '{}'.".format(self.form.__name__))
    mat = COOData._assemble_scipy_csr(*self._assemble(*args, **kwargs))
    logger.info("Assembling finished.")
    return mat