Adding Chapter 3 files

Chapter3/ductyyping/ducttype1.py

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+#ducttype1.py
+class Car:
+    def start(self):
+        print ("start engine by ignition /battery")
+
+class Cycle:
+    def start(self):
+        print ("start by pushing paddles")
+
+class Horse:
+    def start(self):
+        print ("start by pulling/releasing the reins")
+
+
+if __name__ == "__main__":
+    for obj in Car(), Cycle(), Horse():
+        obj.start()