ProjectEuler#37 Truncatable primes

#The number 3797 has an interesting property. Being prime itself, it is
#possible to continuously remove digits from left to right, and remain prime
#at each stage: 3797, 797, 97, and 7. Similarly we can work from right to
#left: 3797, 379, 37, and 3.

#Find the sum of the only eleven primes that are both truncatable from left
#to right and right to left.

#NOTE: 2, 3, 5, and 7 are not considered to be truncatable primes.

def isPrime(n):
    '''check if integer n is a prime'''
    if n < 2:
        return False
    # range starts with 2 and only needs to go up the square-root of n
    for x in range(2, int(n**0.5)+1):
        if n % x == 0:
            return False
    return True

def isTruncPrime(n):
    if n < 10:
        return False
    numStr = str(n)
    while len(numStr) > 1:
        numStr = numStr[1:]
        if not isPrime(int(numStr)):
            return False
    numStr = str(n)
    while len(numStr) > 1:
        numStr = numStr[:len(numStr)-1]
        if not isPrime(int(numStr)):
            return False

    return True

TruncPrimesList = []
i = 3

while len(TruncPrimesList) < 11:
    if isPrime(i) and isTruncPrime(i):
        TruncPrimesList.append(i)
    i += 2

count = 0
for i in TruncPrimesList:
    count += i
print count