Improve solution

Author: MaximSmolskiy

project_euler/problem_058/sol1.py

@@ -33,7 +33,6 @@
 count of current primes.
 
 """
-from math import isqrt
 
 
 def isprime(n: int) -> int:
@@ -52,9 +51,11 @@ def isprime(n: int) -> int:
     if n % 2 == 0 and n > 2:
         return 0
 
-    for i in range(3, isqrt(n) + 1, 2):
+    i = 2
+    while i * i <= n:
         if n % i == 0:
             return 0
+        i += 2
     return 1