Load (Bytes)
Input: excel_bytes → Outputs: sheets dict + original bytes.
List Sheets
Input: excel_bytes → Output: sheet_names (LIST).
Select Sheet
Inputs: excel_bytes, sheet_name → Output: dataframe.
Query Rows
Inputs: dataframe, query → Output: filtered_df.
Get Cell
Inputs: excel_bytes, sheet_name, cell → Output: value.
Eval Formula
Inputs: excel_bytes, sheet_name, cell → Output: formula_result.
Write Cell
Inputs: excel_bytes, sheet_name, cell, value → Output: updated_excel_bytes.
Save Bytes
Input: workbook → Output: excel_bytes.