Just learning Python, wrote a simple test program, found that Python consumes a lot of memory, no free memory in the process of calculation, excuse me what reason?

 #!/usr/local/bin/env python 

Def is_prime (num) : 
If num & lt; 
=1: return FalseIf num!=2 and num % 2==0: return False 

To=num/2 + 1 
For x in range (3, to, 2) : 
If num % x==0: return False 
Return True 

If __name__=="__main__" : 
Primes=[] 
For x in range (2, 100) : 
If is_prime (x) : primes. Append (x) 
Print (primes) 

The product=primes [0] 
For I in range (1, len (primes) : 
Print (" prime: "+ STR (primes [I])) 
New_prime=product * primes [I] + 1 
If is_prime (new_prime) : 
Print (" new prime: "+ STR (new_prime)) 
The else: 
Print (STR (new_prime) + "is not the prime! [error] ") 
The product *=primes [I]