dbshelve.py throws exception: AttributeError: 'DB' object has no attribute '__iter__'

Binary package hint: python2.6

In Python 2.6, the dbshelve.py module throws an AttributeError exception whenever a call is made to a method that depends upon an __iter__ method. The exception is:

  File "/usr/lib/python2.6/bsddb/dbshelve.py", line 167, in __iter__
    return self.db.__iter__()
AttributeError: 'DB' object has no attribute '__iter__'

This means that, if mydb is an istance of a DB object, the following examples will fail:

    for key in mydb: print key

    print (k for k in mydb.iterkeys())

    for k, d in mydb.itervalues(): print k, d

and many other statements depending on iterable(mydb) being true

Note that, in Python 2.5, these examples work and no exception is thrown. In fact, if you have both 2.5 and 2.6 installed on the same system, you can run the same program containing code as above with Python2.5 without issue while running it under Python 2.6 raises the exception seen above.

Python Version:

$ apt-cache policy python2.6
python2.6:
  Installed: 2.6.2-0ubuntu1
  Candidate: 2.6.2-0ubuntu1
  Version table:
 *** 2.6.2-0ubuntu1 0
        500 http://archive.ubuntu.com jaunty/main Packages
        100 /var/lib/dpkg/status

Ubuntu version:
$ lsb_release -rd
Description: Ubuntu 9.04
Release: 9.04

Expected: Python program using dbshelve.py will work without modification under Python versions 2.5 and 2.6

Actual: Python program works under Python2.5 but raises exception under Python 2.6