Doc: Fix GL08 error for pandas.ExcelFile.book (#57807)

* Fix GL08 error for pandas.ExcelFile.book

* fixing NameError("name 'file' is not defined")

* fixing No Such File errors in code example

ci/code_checks.sh

@@ -144,7 +144,6 @@ if [[ -z "$CHECK" || "$CHECK" == "docstrings" ]]; then
 
     MSG='Partially validate docstrings (GL08)' ;  echo $MSG
     $BASE_DIR/scripts/validate_docstrings.py --format=actions --errors=GL08 --ignore_functions \
-        pandas.ExcelFile.book\
         pandas.Index.empty\
         pandas.Index.names\
         pandas.Index.view\

pandas/io/excel/_base.py

@@ -1631,6 +1631,32 @@ def parse(
 
     @property
     def book(self):
+        """
+        Gets the Excel workbook.
+
+        Workbook is the top-level container for all document information.
+
+        Returns
+        -------
+        Excel Workbook
+            The workbook object of the type defined by the engine being used.
+
+        See Also
+        --------
+        read_excel : Read an Excel file into a pandas DataFrame.
+
+        Examples
+        --------
+        >>> file = pd.ExcelFile("myfile.xlsx")  # doctest: +SKIP
+        >>> file.book  # doctest: +SKIP
+        <openpyxl.workbook.workbook.Workbook object at 0x11eb5ad70>
+        >>> file.book.path  # doctest: +SKIP
+        '/xl/workbook.xml'
+        >>> file.book.active  # doctest: +SKIP
+        <openpyxl.worksheet._read_only.ReadOnlyWorksheet object at 0x11eb5b370>
+        >>> file.book.sheetnames  # doctest: +SKIP
+        ['Sheet1', 'Sheet2']
+        """
         return self._reader.book
 
     @property