Primera version

calcoo.py

+#!/usr/bin/python3
+# -*- coding:utf-8 -*-
+
+import sys
+
+
+class Calculadora():
+    def sum(self, a, b):
+        return a + b
+
+    def substraction(self, a, b):
+        return a - b
+
+
+def to_number(num):
+    try:
+        if '.' in num:
+            return float(num)
+        else:
+            return int(num)
+    except:
+        sys.exit("Error")
+
+
+def do_operation(operation, op1, op2):
+    calculator = Calculadora()
+
+
+    if operation == "suma":
+        result = calculator.sum(op1, op2)
+        print(result)
+
+    elif operation == "resta":
+        result = calculator.substraction(op1, op2)
+        print(result)
+
+    else:
+        print ("Not allowed operation", operation)
+
+if __name__ == "__main__":
+    op1 = to_number(sys.argv[1])
+    operation = sys.argv[2]
+    op2 = to_number(sys.argv[3])
+    do_operation(operation, op1, op2)