Currently when I import some code, for example:
from datetime import datetime
I can\'t see what methods it has. How could I know that there
try SublimeJEDI
step 1: ctrl+shift+p search - install package
step 2: Wait for few seconds until drop down box to appear
step 3: search Jedi - Python autocompletion and press enter
now auto completion for python will work in sublime..
Note: you can try Anaconda instead Jedi using same step.
You can have this functionality with the Anaconda Package.

Anaconda includes a lot more features than just auto completetion. You can install the Jedi Package. This is the auto complete that ships with Anaconda.