Add defaults to csv stubs (#9774)

stdlib/_csv.pyi

@@ -43,42 +43,42 @@ class _writer:
 
 def writer(
     csvfile: SupportsWrite[str],
-    dialect: _DialectLike = ...,
+    dialect: _DialectLike = "excel",
     *,
-    delimiter: str = ...,
-    quotechar: str | None = ...,
-    escapechar: str | None = ...,
-    doublequote: bool = ...,
-    skipinitialspace: bool = ...,
-    lineterminator: str = ...,
-    quoting: _QuotingType = ...,
-    strict: bool = ...,
+    delimiter: str = ",",
+    quotechar: str | None = '"',
+    escapechar: str | None = None,
+    doublequote: bool = True,
+    skipinitialspace: bool = False,
+    lineterminator: str = "\r\n",
+    quoting: _QuotingType = 0,
+    strict: bool = False,
 ) -> _writer: ...
 def reader(
     csvfile: Iterable[str],
-    dialect: _DialectLike = ...,
+    dialect: _DialectLike = "excel",
     *,
-    delimiter: str = ...,
-    quotechar: str | None = ...,
-    escapechar: str | None = ...,
-    doublequote: bool = ...,
-    skipinitialspace: bool = ...,
-    lineterminator: str = ...,
-    quoting: _QuotingType = ...,
-    strict: bool = ...,
+    delimiter: str = ",",
+    quotechar: str | None = '"',
+    escapechar: str | None = None,
+    doublequote: bool = True,
+    skipinitialspace: bool = False,
+    lineterminator: str = "\r\n",
+    quoting: _QuotingType = 0,
+    strict: bool = False,
 ) -> _reader: ...
 def register_dialect(
     name: str,
-    dialect: Any = ...,
+    dialect: type[Dialect] = ...,
     *,
-    delimiter: str = ...,
-    quotechar: str | None = ...,
-    escapechar: str | None = ...,
-    doublequote: bool = ...,
-    skipinitialspace: bool = ...,
-    lineterminator: str = ...,
-    quoting: _QuotingType = ...,
-    strict: bool = ...,
+    delimiter: str = ",",
+    quotechar: str | None = '"',
+    escapechar: str | None = None,
+    doublequote: bool = True,
+    skipinitialspace: bool = False,
+    lineterminator: str = "\r\n",
+    quoting: _QuotingType = 0,
+    strict: bool = False,
 ) -> None: ...
 def unregister_dialect(name: str) -> None: ...
 def get_dialect(name: str) -> Dialect: ...