<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def distance_home(GPS_RAW):
    '''distance from first fix point'''
    global first_fix
    if (hasattr(GPS_RAW, 'fix_type') and GPS_RAW.fix_type < 2) or \
       (hasattr(GPS_RAW, 'Status')   and GPS_RAW.Status   < 2):
        return 0

    if first_fix == None:
        first_fix = GPS_RAW
        return 0
    return distance_two(GPS_RAW, first_fix)