this representable base adds generatable __str__ and __repr__

representable_base.py

# based on: https://gist.github.com/exhuma/5935162#file-representable_base-py

class RepresentableBase(object):
    """ Add automatic __repr__ and __str__ to SQLAlchemy ORM models
    """
    def _repr_worker(self, attribute):
        mapper = object_mapper(self)
        items = [(p.key, getattr(self, p.key))
            for p in (
                mapper.get_property_by_column(c)
                for c in getattr(mapper, attribute))]

        return "{0}({1})".format(
            self.__class__.__name__,
            ', '.join(['{0}={1!r}'.format(*attr_pair) for attr_pair in items]))

    def __repr__(self):
        '''This will represent ``self`` as::

            ClassName(pkey_1='value1', pkey_2='value2')

            where ``pkey_1..pkey_n`` are the primary key columns
            of the mapped table
        '''

        return self._repr_worker('primary_key')

    def __str__(self):
        '''This will represent ``self`` as::

            ClassName(column_1='value1', column_2='value2')

            where ``column_1..column_n`` are the all columns
            of the mapped table
        '''

        return self._repr_worker('columns')