* python/py-cmd.c (cmdpy_completer): Use explicit decref.

	* python/py-cmd.c (cmdpy_completer): Use explicit decref.
	* python/py-param.c (get_set_value, get_show_value): Use
	explicit decrefs.
	* python/python.c (start_type_printers, apply_type_printers):
	Use explicit decrefs.