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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 export_to_dict(self, recursive=True, include_parent_ref=False, include_defaults=False):
 """Export obj to dictionary"""

        cls = self.__class__
        parent_excludes = {}
        if recursive and not include_parent_ref:
            parent_ref = cls.__mapper__.relationships.get(cls.export_parent)
            if parent_ref:
                parent_excludes = {c.name for c in parent_ref.local_columns}
        dict_rep = {c.name: getattr(self, c.name)
                    for c in cls.__table__.columns
                    if (c.name in self.export_fields and
                        c.name not in parent_excludes and
                        (include_defaults or (
                            getattr(self, c.name) is not None and
                            (not c.default or
                                getattr(self, c.name) != c.default.arg))))
                    }
        if recursive:
            for c in self.export_children:
                # sorting to make lists of children stable
                dict_rep[c] = sorted(
                    [
                        child.export_to_dict(
                            recursive=recursive,
                            include_parent_ref=include_parent_ref,
                            include_defaults=include_defaults,
                        ) for child in getattr(self, c)
                    ],
                    key=lambda k: sorted(k.items()))

        return dict_rep