>>> import os
>>> import sys
>>> os.path.dirname(sys.executable)
'C:Python25'
python -c "import sys; print(sys.executable)"
import imp
print("Location of Python os module sources:")
print(imp.find_module('os'))
print("
Location of Python time module sources:")
print(imp.find_module('time'))
this video might help: https://youtu.be/PzlQPNNt8T4?t=147
(video starts at 2:27)