当我们打开一个交互式python3解释器并运行一些命令时，是否在某个模块中运行这些命令？

Question

When we open an interactive python3 interpreter and run some commands, do we run the commands in some module? What is that module?

I ask this because __name__ is __main__ in such cases, and I think __name__ is an attribute of some module which I don't know and am asking for. But __dict__ and __file__ as attributes of a module don't exist. The attributes which exist are:

>>> globals()
{'__package__': None, '__doc__': None, '__loader__': <class '_frozen_importlib.BuiltinImporter'>, '__name__': '__main__',   '__builtins__': <module 'builtins' (built-in)>, '__spec__': None}

Answer 1

Yes, the interpreter session is the __main__ module:

$ python3.6
Python 3.6.1 (default, Apr  5 2017, 20:56:42)
[GCC 4.2.1 Compatible Apple LLVM 8.0.0 (clang-800.0.42.1)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.modules['__main__']
<module '__main__' (built-in)>
>>> sys.modules['__main__'].__dict__ is globals()
True

The globals() object is the module __dict__ namespace. Don't confuse the contents of the namespace with the namespace itself (when you ask for the attributes of an instance, __dict__ is not inside the instance __dict__ attribute either ).

The __file__ attribute is optional ; since you are not running from a file here, the attribute is not set:

>>> sys.modules['__main__'].__file__
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: module '__main__' has no attribute '__file__'