statistics: fix median_grouped, NormalDist.samples (#3818)

Author: hauntsaninja

stdlib/3/statistics.pyi

@@ -20,7 +20,7 @@ if sys.version_info >= (3, 6):
 def median(data: Iterable[_Number]) -> _Number: ...
 def median_low(data: Iterable[_Number]) -> _Number: ...
 def median_high(data: Iterable[_Number]) -> _Number: ...
-def median_grouped(data: Iterable[_Number]) -> _Number: ...
+def median_grouped(data: Iterable[_Number], interval: _Number = ...) -> _Number: ...
 def mode(data: Iterable[_Number]) -> _Number: ...
 if sys.version_info >= (3, 8):
     def multimode(data: Iterable[_T]) -> List[_T]: ...
@@ -46,7 +46,7 @@ if sys.version_info >= (3, 8):
         def variance(self) -> float: ...
         @classmethod
         def from_samples(cls: Type[_T], data: Iterable[SupportsFloat]) -> _T: ...
-        def samples(self, n: int, *, seed: Optional[Any]) -> List[float]: ...
+        def samples(self, n: int, *, seed: Optional[Any] = ...) -> List[float]: ...
         def pdf(self, x: float) -> float: ...
         def cdf(self, x: float) -> float: ...
         def inv_cdf(self, p: float) -> float: ...

tests/stubtest_whitelists/py38.txt

@@ -166,7 +166,6 @@ signal.sigtimedwait
 signal.sigwaitinfo
 smtplib.SMTP.sendmail
 sre_constants.RANGE_IGNORE
-statistics.NormalDist.samples
 sys.UnraisableHookArgs
 threading.ExceptHookArgs
 time.CLOCK_PROF

tests/stubtest_whitelists/py3_common.txt

@@ -687,7 +687,6 @@ ssl.SSLSocket.recvfrom
 ssl.SSLSocket.recvfrom_into
 ssl.SSLSocket.sendto
 ssl._ASN1Object.__new__
-statistics.median_grouped
 subprocess.Popen.send_signal
 subprocess.call
 sunau.Au_write.getmark