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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def to_obj(self, ns_info=None):
 """Convert to a GenerateDS binding object. Subclasses can override this function. Returns: An instance of this Entity's ``_binding_class`` with properties set from this Entity. """

        if ns_info:
            ns_info.collect(self)

        # null behavior for classes that inherit from Entity but do not
        # have _binding_class
        if not hasattr(self, "_binding_class"):
            return None

        entity_obj = self._binding_class()

        for field, val in six.iteritems(self._fields):
            # EntityLists with no list items should be dropped
            if isinstance(val, EntityList) and len(val) == 0:
                val = None
            elif field.multiple:
                if val:
                    val = [_objectify(field, x, ns_info) for x in val]
                else:
                    val = []
            else:
                val = _objectify(field, val, ns_info)

            setattr(entity_obj, field.name, val)

        self._finalize_obj(entity_obj)
        return entity_obj