* mi/mi-main.c: Include python-internal.h.

	* mi/mi-main.c: Include python-internal.h.
	(mi_cmd_list_features): Check gdb_python_initialized.
	* python/py-inferior.c (python_on_normal_stop, python_on_resume)
	(python_inferior_exit, python_new_objfile, add_thread_object)
	(delete_thread_object, py_free_inferior): Check
	gdb_python_initialized.
	* python/py-prettyprint.c (apply_val_pretty_printer): Check
	gdb_python_initialized.
	* python/py-type.c (save_objfile_types): Check
	gdb_python_initialized.
	* python/python-internal.h (gdb_python_initialized): Declare.
	* python/python.c (ensure_python_env): Throw exception if
	Python not initialized.
	(before_prompt_hook, source_python_script_for_objfile)
	(start_type_printers, apply_type_printers,
	free_type_printers): Check gdb_python_initialized.
	* varobj.c (varobj_get_display_hint)
	(dynamic_varobj_has_child_method, update_dynamic_varobj_children)
	(install_new_value_visualizer, varobj_set_visualizer)
	(value_get_print_value): Check gdb_python_initialized.