fix the reviewer comment

Author: ebrahimbeiati

Sprint-2/implement_skip_list/skip_list.py

@@ -43,7 +43,10 @@ def _find_position(self, value):
             b = self.skips[i + 1]
 
             node_a = self._get_node(a)
-            node_b = self._get_node(b)
+            node_b = node_a
+            for _ in range(b - a):
+                if node_b:
+                    node_b = node_b.next
 
             if node_a.value <= value < node_b.value:
                 # linear search between a and b
@@ -95,7 +98,10 @@ def __contains__(self, value):
             b = self.skips[i + 1]
 
             node_a = self._get_node(a)
-            node_b = self._get_node(b)
+            node_b = node_a
+            for _ in range(b - a):
+                if node_b:
+                    node_b = node_b.next
 
             if node_a.value <= value < node_b.value:
                 idx = a