Python Dictionary get()

Python dictionary instances have a built in get() method that will return the value of the specified key. The method also accepts a default value to return should the key not exist. Using this method to access dictionary values is handy when you want to set a default. The alternative methods are to either manually test if the key exists or to handle a KeyError exception. The three methods are outlined below.

def use_get():
   dict_obj = dict(a=1, b=2)
   return dict_obj.get("c", 3)

def use_has_key():
   dict_obj = dict(a=1, b=2)
   if dict_obj.has_key("c"):
       return dict_obj["c"]
   else:
       return 3
  
def use_key_error():
   dict_obj = dict(a=1, b=2)
   try:
       return dict_obj["c"]
   except KeyError:
       return 3
  
if __name__ == "__main__":
   print "USE GET:", use_get()
   print "HAS KEY:", use_has_key()
   print "KEY ERROR:", use_key_error()