Type Definition pyo3::ffi::_PyCFunctionFastWithKeywords

pub type _PyCFunctionFastWithKeywords = unsafe extern "C" fn(slf: *mut PyObject, args: *const *mut PyObject, nargs: Py_ssize_t, kwnames: *mut PyObject) -> *mut PyObject;

This is supported on Py_3_7 and non-Py_LIMITED_API only.