add better timing functionality with the datetime library

linalg-practice.py

@@ -1,5 +1,6 @@
 import sympy as sp
 import time
+import datetime
 import random
 import readline
 
@@ -164,7 +165,7 @@ def practice(t) :
                 # increment count
                 count += 1
                 # print success message
-                print("Correct! You have solved", count, "problems in %.2f seconds" %tictoc)
+                print("Correct! You have solved", count, "problems in", str(datetime.timedelta(seconds=round(tictoc))))
                 break
             else :
                 # print failure message