How to dynamically import modules using exec

Question

Now I want to build the get_doc () function, which can get the module doc. Here is the code

def get_doc(module):
    exec "import module"
    print module.__doc__

And the returned information:

Traceback (most recent call last):
  File "<pyshell#36>", line 1, in <module>
    get_doc(sys)
NameError: name 'sys' is not defined

Answer 1

The problem is that you import "module"instead of the specified module, and you did not put the name moduleanywhere. A stupid solution for this would be to always useexec

def get_doc(module):
    exec "import {}".format(module)
    exec "print {}.__doc__".format(module)"

But instead, execI would suggest using a function __import__:

def get_doc(module):
    module = __import__(module)
    print module.__doc__

This allows you to increase flexibility, and you can modify, use the module as you wish.

Answer 2

When you speak

get_doc(sys)

python sys. , , -

• __import__ ,

  def get_doc(module):
      mod = __import__(module)
      print mod.__doc__
  
  get_doc("sys")
  

. , exec , this, , aIKid.