DOC: Fix some docstring validations in pd.Series (#60481)

* DOC: Fix some docstring validations in pd.Series

* new circle

ci/code_checks.sh

@@ -73,8 +73,6 @@ if [[ -z "$CHECK" || "$CHECK" == "docstrings" ]]; then
         -i "pandas.Period.freq GL08" \
         -i "pandas.Period.ordinal GL08" \
         -i "pandas.RangeIndex.from_range PR01,SA01" \
-        -i "pandas.Series.dt.unit GL08" \
-        -i "pandas.Series.pad PR01,SA01" \
         -i "pandas.Timedelta.max PR02" \
         -i "pandas.Timedelta.min PR02" \
         -i "pandas.Timedelta.resolution PR02" \

pandas/core/arrays/datetimelike.py

@@ -2073,7 +2073,29 @@ def _creso(self) -> int:
 
     @cache_readonly
     def unit(self) -> str:
-        # e.g. "ns", "us", "ms"
+        """
+        The precision unit of the datetime data.
+
+        Returns the precision unit for the dtype.
+        It means the smallest time frame that can be stored within this dtype.
+
+        Returns
+        -------
+        str
+            Unit string representation (e.g. "ns").
+
+        See Also
+        --------
+        TimelikeOps.as_unit : Converts to a specific unit.
+
+        Examples
+        --------
+        >>> idx = pd.DatetimeIndex(["2020-01-02 01:02:03.004005006"])
+        >>> idx.unit
+        'ns'
+        >>> idx.as_unit("s").unit
+        's'
+        """
         # error: Argument 1 to "dtype_to_unit" has incompatible type
         # "ExtensionDtype"; expected "Union[DatetimeTZDtype, dtype[Any]]"
         return dtype_to_unit(self.dtype)  # type: ignore[arg-type]