- /* Parse the argument of self.wait() into 'py_conds'. */
- if (!PyArg_ParseTuple(args, "O", &py_conds)) {
+ /*
+ * Parse the argument of self.wait() into 'py_conds', and check
+ * the data type. The argument is optional, None is assumed in
+ * its absence. None or an empty dict or an empty list mean that
+ * there is no condition, and the next available sample shall
+ * get returned to the caller.
+ */
+ py_conds = Py_None;
+ if (!PyArg_ParseTuple(args, "|O", &py_conds)) {