After downloading Tweepy I don't know where to locate it

I have downloaded Tweepy, and I locate its folder in the following path, where I have other libraries such as Pygame and swampy:

C:Python25Libsite-packages

… but when I import it – even in the command line – to make sure that the installation was successfully done, it says:

import tweepy
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:Python25libsite-packagestweepy__init__.py", line 14, in <module>
from tweepy.api import API
File "C:Python25libsite-packagestweepyapi.py", line 8, in <module>
from tweepy.binder import bind_api
File "C:Python25libsite-packagestweepybinder.py", line 22, in <module>
raise ImportError, "Can't load a json library"
ImportError: Can't load a json library