[web2py] AttributeError: type object 'Field' has no attribute 'Method'

[Jeff Kusi]

I am attempting to use the virtual Methods of the dal but I am running into 
this issue. Here's my code
db.define_table('Posts',
                db.Field('zipcode'),
                db.Field.Method('distance',lambda row, loc_zip=33333:abs(row
.zipcode-loc_zip))
                )


But I am running into the following error:
"AttributeError: type object 'Field' has no attribute 'Method'"
I am running  
web2py™(2, 2, 1, datetime.datetime(2012, 10, 21, 16, 57, 4), 
'stable')PythonPython 
2.7.3: /home/yolo/python
Am I doing something wrong?  I looked into the web2py code and all I saw 
the FieldVirtual method definitions( not Field.Virtual as described in the 
book). 
Am I using the wrong version?  Any help would be appreciated.

thanks.

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