Made output_material_module_import_statements public.
Alphabetized class attributes.
Updated TODO.
Changed 'material_definition_module' to 'definition_module'.
Removed MaterialManager property.

Removed MaterialManager._should_have_definition_module.

Use os.path.isfile(manager._definition_module_path) instead.
Cleaning up file read method.
Cleaned up FileManager._execute().
Cleaned up MaterialManager._execute_output_material_module().
Cleaning up MaterialManager.write_output_material().
Cleaning up MaterialManager.write_output_material().
Changed 'output_material_module' to 'output_module'.
Cleaning up MaterialManager method.

MaterialManager._get_output_module_import_statements_and_body_lines().
Removed _should_have_user_input_module from MaterialManager.

Test for _user_input_wrapper_in_memory instead.
Cleaning up MaterialManager method.

MaterialManager._get_output_module_import_statements_and_body_lines().
Made MaterialManager._output_module_import_statements private.
Cleaning up MaterialManager.write_output_material().
Cleaning up MaterialManager.write_output_material().
Cleaning up MaterialManager.write_output_material().
Added FileManager._write() method.
Added Controller._unicode_directive property.