Lab Four Solution Optimized

def palindromesBelow(cap):
   for x in [i for i in range(10) if i <= cap]:
      yield x

end = '1'
   shouldContinue = True

while shouldContinue:
      if int(end[0]) % 2 == 0 or int(end[-1]) % 2 == 0:
         end = str(int(end) + 1)
         continue

shouldContinue = False

for middle in ['', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9']:
         val = int(end + middle + end[::-1])

if val <= cap:
            shouldContinue = True
            yield val

end = str(int(end) + 1)
            
            
primesSoFar = [2,3]
def isPrime(n):
   global primesSoFar

if n < 2:
      return False
   if n in primesSoFar:
      return True

# compute the primes up to sqrt(n) 
   next = primesSoFar[-1] + 2
   while next * next <= n:
      isPrime = True

for p in primesSoFar:
         if next % p == 0:
            isPrime = False

if isPrime:
         primesSoFar.append(next)

next = next + 2

return not any([n % x == 0 for x in primesSoFar])

def palindromePrimesBelow(cap):
   return sorted([x for x in palindromesBelow(cap) if isPrime(x)])

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