If I understand right, you want open the interpreter and call the functions from that py script. To doing so in python 2.7 you should do two thing, go in the directory where the .py file reside and save and empty text file named:
__init__.py
this tell the interpreter the files in that directory are good to import then use
import pdbtools
as the first thing you do opening a new interpreter, this import that file and all the function inside it, making them ready to use from the interpreter prompt