The functions in this section are always available to the interpreter and are contained within the __builtin__ module. In addition, the __builtins__ attribute of each module usually refers to this module.
By default, the _ variable is set to the result of the last expression evaluated when the interpreter is running in interactive mode.
sys.displayhook (p. 166)
__import__(name [, globals [, locals [, fromlist]]])
This function is invoked by the import statement to load a module. name is a string containing the module name, globals is an optional dictionary defining the global namespace, locals is a dictionary defining the local namespace, and fromlist is a list of targets given to the from statement. ...