Regular Expression - newbie question

[SK]

I want to parse a file for the following:-

Line containing "python output" followed by anything and then "Hello
World"
The following code snippet works fine but How do I know that two such
patterns exist in the file.

Is it possible to mask the *anything* to be output on match.group()
i.e. The output should NOT have "This is my file"

I want something like this:- 

Desired Output:-
==============

Pattern 1

This is one python output
Hello World

Pattern 2

This is two python output
Hello World

Total matches found is 2.

PS: Also, my regular expression is determined dynamically by the user.


Code Snippet
============

import re
data = open("c.txt","rb").read()
regexp = "^.*python output[\000-\377]*^.*Hello World[\000-\377].*$"
r = re.compile(regexp,re.M)
match = re.search(r, data)
print match.group()

c.txt
=====

This is my file
This is one python output
This is my file
This is my file
Hello World
This is my file
This is two python output
This is my file
Hello World


Output
======
This is one python output
This is my file
This is my file
Hello World
This is my file
This is two python output
This is my file
Hello World

Thanks in Advance