human
Here's a good function header given the following:
I wrote the below code

    def get_ha1(realm, username):
        result = None
        f = open(filename, 'r')
        for line in f:
            (u, r, ha1) = line.rstrip().split(':')
            if ((u == username) and (r == realm)):
                result = ha1
                break
        f.close()
        return result
    return get_ha1

What's a good function header?
assistant
#Here's a good function header.

def get_ha1_file_htdigest(filename):