diff --git a/stdlib/2and3/modulefinder.pyi b/stdlib/2and3/modulefinder.pyi
index 4c4962843..a3df358b5 100644
--- a/stdlib/2and3/modulefinder.pyi
+++ b/stdlib/2and3/modulefinder.pyi
@@ -1,4 +1,4 @@
-
+import sys
 from typing import Optional, Container, Dict, Sequence, Tuple, List, Any, Iterator, IO, Iterable
 from types import CodeType
 
@@ -29,7 +29,10 @@ class ModuleFinder:
     excludes: Container[str]  # undocumented
     replace_paths: Sequence[Tuple[str, str]]  # undocumented
 
-    def __init__(self, path: Optional[List[str]] = ..., debug: int = ..., excludes: Container[str] = ..., replace_paths: Sequence[Tuple[str, str]] = ...) -> None: ...
+    if sys.version_info >= (3, 8):
+        def __init__(self, path: Optional[List[str]] = ..., debug: int = ..., excludes: Optional[Container[str]] = ..., replace_paths: Optional[Sequence[Tuple[str, str]]] = ...) -> None: ...
+    else:
+        def __init__(self, path: Optional[List[str]] = ..., debug: int = ..., excludes: Container[str] = ..., replace_paths: Sequence[Tuple[str, str]] = ...) -> None: ...
     def msg(self, level: int, str: str, *args: Any) -> None: ...  # undocumented
     def msgin(self, *args: Any) -> None: ...  # undocumented
     def msgout(self, *args: Any) -> None: ...  # undocumented
@@ -43,7 +46,8 @@ class ModuleFinder:
     def find_all_submodules(self, m: Module) -> Iterable[str]: ...  # undocumented
     def import_module(self, partname: str, fqname: str, parent: Module) -> Optional[Module]: ...  # undocumented
     def load_module(self, fqname: str, fp: IO[str], pathname: str, file_info: Tuple[str, str, str]) -> Module: ...  # undocumented
-    def scan_opcodes(self, co: CodeType) -> Iterator[Tuple[str, Tuple[Any, ...]]]: ...  # undocumented
+    if sys.version_info >= (3, 6):
+        def scan_opcodes(self, co: CodeType) -> Iterator[Tuple[str, Tuple[Any, ...]]]: ...  # undocumented
     def scan_code(self, co: CodeType, m: Module) -> None: ...  # undocumented
     def load_package(self, fqname: str, pathname: str) -> Module: ...  # undocumented
     def add_module(self, fqname: str) -> Module: ...  # undocumented
diff --git a/tests/stubtest_whitelists/py35.txt b/tests/stubtest_whitelists/py35.txt
index cff477e3e..a34230f81 100644
--- a/tests/stubtest_whitelists/py35.txt
+++ b/tests/stubtest_whitelists/py35.txt
@@ -62,7 +62,6 @@ macpath.split
 macpath.splitdrive
 macpath.splitext
 mmap.ACCESS_DEFAULT
-modulefinder.ModuleFinder.scan_opcodes
 multiprocessing.context.BaseContext.reducer
 multiprocessing.shared_memory
 os.DirEntry
diff --git a/tests/stubtest_whitelists/py38.txt b/tests/stubtest_whitelists/py38.txt
index a427bb570..4701a7506 100644
--- a/tests/stubtest_whitelists/py38.txt
+++ b/tests/stubtest_whitelists/py38.txt
@@ -130,7 +130,6 @@ mmap.MADV_NOCORE
 mmap.MADV_NOSYNC
 mmap.MADV_PROTECT
 mmap.MADV_SOFT_OFFLINE
-modulefinder.ModuleFinder.__init__
 multiprocessing.pool.CLOSE
 multiprocessing.pool.RUN
 multiprocessing.pool.TERMINATE