Fill form values in a web page via a Python script (not testing)

You are looking for Mechanize

Form submitting sample:

import re
from mechanize import Browser

br = Browser()
br.open("http://www.example.com/")
br.select_form(name="order")
# Browser passes through unknown attributes (including methods)
# to the selected HTMLForm (from ClientForm).
br["cheeses"] = ["mozzarella", "caerphilly"]  # (the method here is __setitem__)
response = br.submit()  # submit current form