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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 get_container_or_none(self, type_):
 """ Returns reference to the class declaration or None. """


        type_ = type_traits.remove_alias(type_)
        type_ = type_traits.remove_cv(type_)

        utils.loggers.queries_engine.debug(
            "Container traits: cleaned up search %s", type_)

        if isinstance(type_, cpptypes.declarated_t):
            cls_declaration = type_traits.remove_alias(type_.declaration)
        elif isinstance(type_, class_declaration.class_t):
            cls_declaration = type_
        elif isinstance(type_, class_declaration.class_declaration_t):
            cls_declaration = type_
        else:
            utils.loggers.queries_engine.debug(
                "Container traits: returning None, type not known\n")
            return

        if not cls_declaration.name.startswith(self.name() + '<'):
            utils.loggers.queries_engine.debug(
                "Container traits: returning None, " +
                "declaration starts with " + self.name() + '<\n')
            return

        # When using libstd++, some container traits are defined in
        # std::tr1::. See remove_template_defaults_tester.py.
        # In this case the is_defined_in_xxx test needs to be done
        # on the parent
        decl = cls_declaration
        if isinstance(type_, class_declaration.class_declaration_t):
            is_ns = isinstance(type_.parent, namespace.namespace_t)
            if is_ns and type_.parent.name == "tr1":
                decl = cls_declaration.parent
        elif isinstance(type_, cpptypes.declarated_t):
            is_ns = isinstance(type_.declaration.parent, namespace.namespace_t)
            if is_ns and type_.declaration.parent.name == "tr1":
                decl = cls_declaration.parent

        for ns in std_namespaces:
            if traits_impl_details.impl_details.is_defined_in_xxx(ns, decl):
                utils.loggers.queries_engine.debug(
                    "Container traits: get_container_or_none() will return " +
                    cls_declaration.name)
                # The is_defined_in_xxx check is done on decl, but we return
                # the original declation so that the rest of the algorithm
                # is able to work with it.
                return cls_declaration

        # This should not happen
        utils.loggers.queries_engine.debug(
            "Container traits: get_container_or_none() will return None\n")