How to use the mypy.nodes.TypeInfo function in mypy

if '.' in name:
                module_name = name.rsplit('.', 1)[0]
            else:
                module_name = '__main__'

        if typevars:
            v = []  # type: List[TypeVarDef]
            for id, n in enumerate(typevars, 1):
                if variances:
                    variance = variances[id - 1]
                else:
                    variance = COVARIANT
                v.append(TypeVarDef(n, id, [], self.o, variance=variance))
            class_def.type_vars = v

        info = TypeInfo(SymbolTable(), class_def, module_name)
        if mro is None:
            mro = []
            if name != 'builtins.object':
                mro.append(self.oi)
        info.mro = [info] + mro
        if bases is None:
            if mro:
                # By default, assume that there is a single non-generic base.
                bases = [Instance(mro[0], [])]
            else:
                bases = []
        info.bases = bases

        return info

def create_new_manager_class_from_from_queryset_method(ctx: DynamicClassDefContext) -> None:
    semanal_api = helpers.get_semanal_api(ctx)

    callee = ctx.call.callee
    assert isinstance(callee, MemberExpr)
    assert isinstance(callee.expr, RefExpr)

    base_manager_info = callee.expr.node
    if base_manager_info is None:
        if not semanal_api.final_iteration:
            semanal_api.defer()
        return

    assert isinstance(base_manager_info, TypeInfo)
    new_manager_info = semanal_api.basic_new_typeinfo(ctx.name,
                                                      basetype_or_fallback=Instance(base_manager_info,
                                                                                    [AnyType(TypeOfAny.unannotated)]))
    new_manager_info.line = ctx.call.line
    new_manager_info.defn.line = ctx.call.line
    new_manager_info.metaclass_type = new_manager_info.calculate_metaclass_type()

    current_module = semanal_api.cur_mod_node
    current_module.names[ctx.name] = SymbolTableNode(GDEF, new_manager_info,
                                                     plugin_generated=True)
    passed_queryset = ctx.call.args[0]
    assert isinstance(passed_queryset, NameExpr)

    derived_queryset_fullname = passed_queryset.fullname
    assert derived_queryset_fullname is not None

def is_normal_type(self, type: mypy.types.Type) -> bool:
        return isinstance(type, mypy.nodes.TypeInfo)

def visit_class_def(self, cdef: ClassDef) -> None:
        self.sem.check_no_global(cdef.name, cdef)
        cdef.fullname = self.sem.qualified_name(cdef.name)
        info = TypeInfo(SymbolTable(), cdef)
        info.set_line(cdef.line)
        cdef.info = info
        self.sem.globals[cdef.name] = SymbolTableNode(GDEF, info,
                                                      self.sem.cur_mod_id)
        self.process_nested_classes(cdef)

def named_type(self, name: str) -> Instance:
        """Return an instance type with type given by the name and no
        type arguments. For example, named_type('builtins.object')
        produces the object type.
        """
        # Assume that the name refers to a type.
        sym = self.lookup_qualified(name)
        return Instance(cast(TypeInfo, sym.node), [])

def builtin_type(self, name: str, args: Optional[List[Type]] = None) -> Instance:
        names = self.modules['builtins']
        sym = names.names[name]
        node = sym.node
        assert isinstance(node, TypeInfo)
        if args:
            # TODO: assert len(args) == len(node.defn.type_vars)
            return Instance(node, args)
        any_type = AnyType(TypeOfAny.special_form)
        return Instance(node, [any_type] * len(node.defn.type_vars))

# bases, which causes the mro to change. If we recomputed our
        # mro, we would compute the *new* mro, which leaves us with no
        # way to detect that the mro has changed! Thus we need to make
        # sure to load the original mro so that once the class is
        # rechecked, it can tell that the mro has changed.
        ti._mro_refs = data['mro']
        ti.tuple_type = (None if data['tuple_type'] is None
                         else mypy.types.TupleType.deserialize(data['tuple_type']))
        ti.typeddict_type = (None if data['typeddict_type'] is None
                            else mypy.types.TypedDictType.deserialize(data['typeddict_type']))
        ti.metadata = data['metadata']
        set_flags(ti, data['flags'])
        return ti


class FakeInfo(TypeInfo):
    # types.py defines a single instance of this class, called types.NOT_READY.
    # This instance is used as a temporary placeholder in the process of de-serialization
    # of 'Instance' types. The de-serialization happens in two steps: In the first step,
    # Instance.type is set to NOT_READY. In the second step (in fixup.py) it is replaced by
    # an actual TypeInfo. If you see the assertion error below, then most probably something
    # went wrong during the second step and an 'Instance' that raised this error was not fixed.
    # Note:
    # 'None' is not used as a dummy value for two reasons:
    # 1. This will require around 80-100 asserts to make 'mypy --strict-optional mypy'
    #    pass cleanly.
    # 2. If NOT_READY value is accidentally used somewhere, it will be obvious where the value
    #    is from, whereas a 'None' value could come from anywhere.
    #
    # Additionally, this serves as a more general-purpose placeholder
    # for missing TypeInfos in a number of places where the excuses
    # for not being Optional are a little weaker.

msg.fail(messages.CANNOT_ASSIGN_TO_TYPE, context)

    if itype.type.is_enum and not (is_lvalue or is_decorated or is_method):
        return itype

    t = node.type
    if t:
        if isinstance(t, PartialType):
            return handle_partial_attribute_type(t, is_lvalue, msg, node.node)
        is_classmethod = is_decorated and cast(Decorator, node.node).func.is_class
        return add_class_tvars(t, itype.type, is_classmethod, builtin_type)
    elif isinstance(node.node, Var):
        not_ready_callback(name, context)
        return AnyType()

    if isinstance(node.node, TypeInfo):
        return type_object_type(node.node, builtin_type)

    if isinstance(node.node, MypyFile):
        # Reference to a module object.
        return builtin_type('builtins.module')

    if is_decorated:
        # TODO: Return type of decorated function. This is quick hack to work around #998.
        return AnyType()
    else:
        return function_type(cast(FuncBase, node.node), builtin_type('builtins.function'))

def visit_class_def(self, cdef: ClassDef) -> None:
        kind = self.kind_by_scope()
        if kind == LDEF:
            return
        elif kind == GDEF:
            self.sem.check_no_global(cdef.name, cdef)
        cdef.fullname = self.sem.qualified_name(cdef.name)
        info = TypeInfo(SymbolTable(), cdef, self.sem.cur_mod_id)
        info.set_line(cdef.line, cdef.column)
        cdef.info = info
        if kind == GDEF:
            self.sem.globals[cdef.name] = SymbolTableNode(kind, info)
        self.process_nested_classes(cdef)

def add_new_class_for_module(module: MypyFile, name: str, bases: List[Instance],
                             fields: 'OrderedDict[str, MypyType]') -> TypeInfo:
    new_class_unique_name = checker.gen_unique_name(name, module.names)

    # make new class expression
    classdef = ClassDef(new_class_unique_name, Block([]))
    classdef.fullname = module.fullname() + '.' + new_class_unique_name

    # make new TypeInfo
    new_typeinfo = TypeInfo(SymbolTable(), classdef, module.fullname())
    new_typeinfo.bases = bases
    calculate_mro(new_typeinfo)
    new_typeinfo.calculate_metaclass_type()

    def add_field_to_new_typeinfo(var: Var, is_initialized_in_class: bool = False,
                                  is_property: bool = False) -> None:
        var.info = new_typeinfo
        var.is_initialized_in_class = is_initialized_in_class
        var.is_property = is_property
        var._fullname = new_typeinfo.fullname() + '.' + var.name()
        new_typeinfo.names[var.name()] = SymbolTableNode(MDEF, var)

    # add fields
    var_items = [Var(item, typ) for item, typ in fields.items()]
    for var_item in var_items:
        add_field_to_new_typeinfo(var_item, is_property=True)