diff --git a/mypy_django_plugin/helpers.py b/mypy_django_plugin/helpers.py
index 1ec3e31..d4b06b8 100644
--- a/mypy_django_plugin/helpers.py
+++ b/mypy_django_plugin/helpers.py
@@ -2,7 +2,6 @@ import typing
 from collections import OrderedDict
 from typing import Dict, Optional, cast
 
-from mypy.checker import TypeChecker, gen_unique_name
 from mypy.mro import calculate_mro
 from mypy.nodes import (
     AssignmentStmt, ClassDef, Expression, ImportedName, Lvalue, MypyFile, NameExpr, SymbolNode, TypeInfo,
@@ -12,6 +11,9 @@ from mypy.types import (
     AnyType, Instance, NoneTyp, Type, TypeOfAny, TypeVarType, UnionType,
     TupleType, TypedDictType)
 
+if typing.TYPE_CHECKING:
+    from mypy.checker import TypeChecker
+
 MODEL_CLASS_FULLNAME = 'django.db.models.base.Model'
 FIELD_FULLNAME = 'django.db.models.fields.Field'
 CHAR_FIELD_FULLNAME = 'django.db.models.fields.CharField'
@@ -165,7 +167,7 @@ def get_argument_type_by_name(ctx: typing.Union[FunctionContext, MethodContext],
     return arg_types[0]
 
 
-def get_setting_expr(api: TypeChecker, setting_name: str) -> Optional[Expression]:
+def get_setting_expr(api: 'TypeChecker', setting_name: str) -> Optional[Expression]:
     try:
         settings_sym = api.modules['django.conf'].names['settings']
     except KeyError:
@@ -314,11 +316,12 @@ def is_foreign_key(t: Type) -> bool:
     return has_any_of_bases(t.type, (FOREIGN_KEY_FULLNAME, ONETOONE_FIELD_FULLNAME))
 
 
-def build_class_with_annotated_fields(api: TypeChecker, base: Type, fields: 'OrderedDict[str, Type]',
+def build_class_with_annotated_fields(api: 'TypeChecker', base: Type, fields: 'OrderedDict[str, Type]',
                                       name: str) -> Instance:
     """Build an Instance with `name` that contains the specified `fields` as attributes and extends `base`."""
     # Credit: This code is largely copied/modified from TypeChecker.intersect_instance_callable and
     # NamedTupleAnalyzer.build_namedtuple_typeinfo
+    from mypy.checker import gen_unique_name
 
     cur_module = cast(MypyFile, api.scope.stack[0])
     gen_name = gen_unique_name(name, cur_module.names)
@@ -348,7 +351,7 @@ def build_class_with_annotated_fields(api: TypeChecker, base: Type, fields: 'Ord
     return Instance(info, [])
 
 
-def make_named_tuple(api: TypeChecker, fields: 'OrderedDict[str, Type]', name: str) -> Type:
+def make_named_tuple(api: 'TypeChecker', fields: 'OrderedDict[str, Type]', name: str) -> Type:
     if not fields:
         # No fields specified, so fallback to a subclass of NamedTuple that allows
         # __getattr__ / __setattr__ for any attribute name.
@@ -363,13 +366,13 @@ def make_named_tuple(api: TypeChecker, fields: 'OrderedDict[str, Type]', name: s
     return TupleType(list(fields.values()), fallback=fallback)
 
 
-def make_typeddict(api: TypeChecker, fields: 'OrderedDict[str, Type]', required_keys: typing.Set[str]) -> Type:
+def make_typeddict(api: 'TypeChecker', fields: 'OrderedDict[str, Type]', required_keys: typing.Set[str]) -> Type:
     object_type = api.named_generic_type('mypy_extensions._TypedDict', [])
     typed_dict_type = TypedDictType(fields, required_keys=required_keys, fallback=object_type)
     return typed_dict_type
 
 
-def make_tuple(api: TypeChecker, fields: typing.List[Type]) -> Type:
+def make_tuple(api: 'TypeChecker', fields: typing.List[Type]) -> Type:
     implicit_any = AnyType(TypeOfAny.special_form)
     fallback = api.named_generic_type('builtins.tuple', [implicit_any])
     return TupleType(fields, fallback=fallback)
diff --git a/mypy_django_plugin/main.py b/mypy_django_plugin/main.py
index f004dfa..00e5d8e 100644
--- a/mypy_django_plugin/main.py
+++ b/mypy_django_plugin/main.py
@@ -2,7 +2,6 @@ import os
 from functools import partial
 from typing import Callable, Dict, Optional, Union, cast
 
-from mypy.checker import TypeChecker
 from mypy.nodes import MemberExpr, NameExpr, TypeInfo
 from mypy.options import Options
 from mypy.plugin import (
@@ -55,6 +54,8 @@ def transform_form_class(ctx: ClassDefContext) -> None:
 
 
 def determine_proper_manager_type(ctx: FunctionContext) -> Type:
+    from mypy.checker import TypeChecker
+
     api = cast(TypeChecker, ctx.api)
     ret = ctx.default_return_type
     if not api.tscope.classes:
@@ -104,6 +105,8 @@ def set_first_generic_param_as_default_for_second(fullname: str, ctx: AnalyzeTyp
 
 
 def return_user_model_hook(ctx: FunctionContext) -> Type:
+    from mypy.checker import TypeChecker
+
     api = cast(TypeChecker, ctx.api)
     setting_expr = helpers.get_setting_expr(api, 'AUTH_USER_MODEL')
     if setting_expr is None:
@@ -183,6 +186,8 @@ class ExtractSettingType:
         self.module_fullname = module_fullname
 
     def __call__(self, ctx: AttributeContext) -> Type:
+        from mypy.checker import TypeChecker
+
         api = cast(TypeChecker, ctx.api)
         original_module = api.modules.get(self.module_fullname)
         if original_module is None: