Question

I’ve got a class that I’m trying to write called dbObject and I’m trying to import it from a script in a different folder. My structure is as follows:

/var/www/html/py/testobj.py

/var/www/html/py/obj/dbObject.py

/var/www/html/py/obj/__init__.py

Now, __init__.py is an empty file. Here are the contents of dbObject.py:

class dbObject:
        def __init__():
                print "Constructor?"

        def test():
                print "Testing"

And here’s the contents of testobj.py:

#!/usr/bin/python
import sys
sys.path.append("/var/www/html/py")
import obj.dbObject

db = dbObject()

When I run this, I get:

Traceback (most recent call last):
  File "testobj.py", line 7, in <module>
    db = dbObject()
NameError: name 'dbObject' is not defined

I’m new to Python, so I’m very confused as to what I’m doing wrong. Could someone please point me in the right direction?

EDIT: Thanks to Martijn Pieters’ answer I modified my testobj.py as follows:

#!/usr/bin/python
import sys
sys.path.append("/var/www/html/py")
sys.path.append("/var/www/html/py/dev")
from  obj.dbObject import dbObject

db = dbObject()

However, now when I run it I get this error:

Traceback (most recent call last):
  File "testobj.py", line 7, in <module>
    db = dbObject()
TypeError: __init__() takes no arguments (1 given)

Is this referring to my init.py or the constructor within dbObject?

EDIT(2): Solved that one myself, the constructor must be able to take at least one parameter – a reference to itself. Simple fix. Looks like this problem is solved!

EDIT (Final): This is nice – I can cut out the import sys and sys.path.append lines and it still works in this instance. Lovely.

Answer 1

You need to import the class from the module:

from obj.dbObject import dbObject

This adds the class dbObject directly to your local namespace.

Your statement import obj.dbObject adds the name obj to the local namespace, so you could also do this instead:

db = obj.dbObject.dbObject()

because obj.dbObject is the dbObject.py module in your obj package directory.