Question

Whenever I try to add triple into the store using following code it gives me following error. Could you please help me in this regard. Thanks in advance.

store = plugin.get('IOMemory',Store)()
store.add((abc, FOAF['knows'],def))

Error:

Traceback (most recent call last):
  File "C:\Python27\internetcode.py", line 114, in <module>
  store.add((abc, FOAF['knows'],def))
TypeError: add() takes at least 3 arguments (2 given)

Answer 1

So first, you need to know that when python says that a method takes 3 arguments, it really means two argument plus the instance argument (usually self). You are currently passing the instance (store) plus a three element tuple: (abc, FOAF['knows'], def), which counts as one argument. store.add() needs a third argument. That’s what the error message is trying to tell you. I don’t know what it needs, but the documentation should be able to explain further.

If nothing else, you can try store.add((abc, FOAF['knows'], def), None), and see if that causes a new error.