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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 generate_signature_class(cls):
 """ Generate a declarative model for storing signatures related to the given cls parameter. :param class cls: The declarative model to generate a signature class for. :return: The signature class, as a declarative derived from Base. """

    return type("%sSigs" % cls.__name__, (Base,),
                {'__tablename__': "%s_sigs" % cls.__tablename__,
                 'id': sa.Column(sa.Integer,
                                 sa.Sequence('%s_id_seq' % cls.__tablename__),
                                 primary_key=True,
                                 doc="primary key"),
                 'data': sa.Column(sa.Text(), nullable=False,
                                   doc="The signed data"),
                 '%s_id' % cls.__tablename__: sa.Column(sa.Integer,
                                                        sa.ForeignKey("%s.id" % cls.__tablename__),
                                                        nullable=False)})