BUG: fix bug with openpyxl on read_only mode

Co-Authored-By: Dacops <[email protected]>

Author: diogomsmiranda

pandas/io/excel/_base.py

@@ -514,17 +514,14 @@ def read_excel(
     if engine_kwargs is None:
         engine_kwargs = {}
 
-        # set to false so cells have a comment attribute
-        if notes is not None and engine == "openpyxl":
-            engine_kwargs = {"read_only": False}
-
     if not isinstance(io, ExcelFile):
         should_close = True
         io = ExcelFile(
             io,
             storage_options=storage_options,
             engine=engine,
             engine_kwargs=engine_kwargs,
+            notes=notes,
         )
     elif engine and engine != io.engine:
         raise ValueError(
@@ -1574,6 +1571,8 @@ class ExcelFile:
     {storage_options}
     engine_kwargs : dict, optional
         Arbitrary keyword arguments passed to excel engine.
+    notes : DataFrame, default None
+        DataFrame that holds notes of the Excel file.
 
     See Also
     --------
@@ -1609,6 +1608,7 @@ def __init__(
         engine: str | None = None,
         storage_options: StorageOptions | None = None,
         engine_kwargs: dict | None = None,
+        notes: DataFrame | None = None,
     ) -> None:
         if engine_kwargs is None:
             engine_kwargs = {}
@@ -1655,6 +1655,10 @@ def __init__(
         self.engine = engine
         self.storage_options = storage_options
 
+        # set so the engine can access the notes from a cell
+        if notes is not None and engine == "openpyxl":
+            engine_kwargs.update({"read_only": False})
+
         self._reader = self._engines[engine](
             self._io,
             storage_options=storage_options,

pandas/io/excel/_openpyxl.py

@@ -542,8 +542,8 @@ def _write_cells(
         if notes is None or notes_col is None:
             return
 
-        for row_idx, (_, row) in enumerate(notes.iterrows()):
-            for col_idx, note in enumerate(row):
+        for row_idx, (_, val) in enumerate(notes.iterrows()):
+            for col_idx, note in enumerate(val):
                 xcell = wks.cell(
                     row=row_idx + 2,  # openpyxl starts counting at 1, not 0
                     column=col_idx + notes_col,

pandas/io/formats/excel.py

@@ -884,7 +884,8 @@ def get_formatted_cells(self) -> Iterable[ExcelCell]:
             yield cell
 
     def get_notes(self) -> Iterable[str]:
-        yield from self.notes.iterrows()
+        if self.notes:
+            yield from self.notes.iterrows()
 
     @doc(storage_options=_shared_docs["storage_options"])
     def write(

pandas/io/formats/style.py

@@ -82,25 +82,8 @@
 
     from pandas import ExcelWriter
 
-try:
-    import matplotlib as mpl
-    import matplotlib.pyplot as plt
-
-    has_mpl = True
-except ImportError:
-    has_mpl = False
-
 import textwrap
 
-
-@contextmanager
-def _mpl(func: Callable) -> Generator[tuple[Any, Any], None, None]:
-    if has_mpl:
-        yield plt, mpl
-    else:
-        raise ImportError(f"{func.__name__} requires matplotlib.")
-
-
 ####
 # Shared Doc Strings