pep style and fixed exception on input other and integer type

dynamic_programming/fibonacci.py

@@ -1,10 +1,12 @@
 """
 This is a pure Python implementation of Dynamic Programming solution to the fibonacci sequence problem.
 """
-class Fibonacci:
 
+
+class Fibonacci:
     def __init__(self, N=None):
         if N:
+            N = int(N)
             self.fib_array = [0] * (N + 1)
             self.fib_array[0] = 0
             self.fib_array[1] = 1
@@ -43,6 +45,7 @@ if __name__ == '__main__':
             "\n********* Enter different values to get the corresponding fibonacci sequence, enter any negative number to exit. ************\n")
         while True:
             print("Enter value: ", end=" ")
+            try:
                 i = eval(input())
                 if i < 0:
                     print("\n********* Good Bye!! ************\n")