refactoring: renamed sqrt function to better fit .math function name

src/main/py/logarithmic_and_expo_and_root_calculations.py

@@ -1,5 +1,5 @@
 import math
 
 
-def sqr(first_number):
+def sqrt(first_number):
     return math.sqrt(first_number)

src/test/py/logarithmic_ann_expo_and_root_calculations.py

@@ -9,8 +9,8 @@ class primitive_calculations(unittest.TestCase):
     def tearDown(self):
         pass
 
-    def test_sqr_of_4_equals_2(self):
-        self.assertEqual(sqr(4), 2)
+    def test_sqrt_of_4_equals_2(self):
+        self.assertEqual(sqrt(4), 2)
 
 
 if __name__ == "__main__":