add some properties and overloads

.github/stubtest-allowlist

@@ -14,6 +14,7 @@ netCDF4.FiltersDict
 netCDF4.SzipInfo
 netCDF4.BloscInfo
 netCDF4.BoolInt
+netCDF4.GetSetItemKey
 netCDF4.T_Datatype
 netCDF4.T_DatatypeNC
 netCDF4.Dataset.__dealloc

src/netCDF4/__init__.pyi

@@ -555,6 +555,14 @@ class _Variable:
 
     def __init__(self, dset: Dataset, varname: str, var: Variable[Any], recdimname: str) -> None: ...
 
+    # shape, ndim, and name actually come from __getattr__
+    @property
+    def shape(self) -> tuple[int, ...]: ...
+    @property
+    def ndim(self) -> int: ...
+    @property
+    def name(self) -> str: ...
+
     def typecode(self) -> np.dtype | type[str]: ...
     def ncattrs(self) -> list[str]: ...
     def _shape(self) -> tuple[int, ...]: ...
@@ -582,9 +590,38 @@ class MFTime(_Variable):
     def __getitem__(self, elem: GetSetItemKey) -> np.ndarray: ...
 
 
-def stringtoarr(string, NUMCHARS: int, dtype: Literal['S', 'U'] = 'S') -> np.ndarray: ...
-def stringtochar(a, encoding: str | bytes | None = 'utf-8') -> np.ndarray: ...
-def chartostring(b, encoding: str | bytes | None = 'utf-8') -> np.ndarray: ...
+@overload
+def stringtoarr(
+    string: str,
+    NUMCHARS: int,
+    dtype: Literal["S"] | np.dtype[np.bytes_]= "S",
+) -> npt.NDArray[np.bytes_]: ...
+@overload
+def stringtoarr(
+    string: str,
+    NUMCHARS: int,
+    dtype: Literal["U"] | np.dtype[np.str_],
+) -> npt.NDArray[np.str_]: ...
+@overload
+def stringtochar(
+    a: npt.NDArray[np.character],
+    encoding: Literal["none", "None", "bytes"],
+) -> npt.NDArray[np.bytes_]: ...
+@overload
+def stringtochar(
+    a: npt.NDArray[np.character],
+    encoding: str = ...,
+) -> npt.NDArray[np.str_] | npt.NDArray[np.bytes_]: ...
+@overload
+def chartostring(
+    b: npt.NDArray[np.character],
+    encoding: Literal["none", "None", "bytes"] = ...,
+) -> npt.NDArray[np.bytes_]: ...
+@overload
+def chartostring(
+    b: npt.NDArray[np.character],
+    encoding: str = ...,
+) -> npt.NDArray[np.str_] | npt.NDArray[np.bytes_]: ...
 
 def getlibversion() -> str: ...