method for finding phone number permutations

import itertools

def findPhoneNumbers(phone_name):
   
    PHONE_LENGTH = 10
    allowed_numbers = ["1","2","3","4","5","6","7","8","9","0"]

    # Get all permutations for positions not taken by phone name
    match_length = PHONE_LENGTH - len(phone_name)
    matches = itertools.permutations(allowed_numbers ,match_length)
    phone_numbers = []

    # Get all permutations that include the phone name
    for m in matches:
        match = list(m) 
        for i in range(len(match) +1):
            phone_number = list(match)
            phone_number.insert(i, phone_name)  
            phone_number = ''.join(phone_number)
            phone_numbers.append(str(phone_number))
    return phone_numbers
    
vishal_phone_numbers = findPhoneNumbers("847425")

print "There are %s matches:" % len(vishal_phone_numbers)
for n in vishal_phone_numbers:
    print n