[ET] Add csv_path to inspector_cli

Per https://fb.workplace.com/groups/pytorch.edge.users/posts/1640064163530537/?comment_id=1640127190190901

Differential Revision: [D66379005](https://our.internmc.facebook.com/intern/diff/D66379005/)

[ghstack-poisoned]

devtools/inspector/_inspector.py

@@ -1173,6 +1173,33 @@ def print_data_tabular(
 
         display_or_print_df(filtered_column_df, file)
 
+
+    def save_data_to_csv(
+        self,
+        file: IO[str],
+    ) -> None:
+        """
+        Stores the underlying EventBlocks in a csv format with tab separator, to facilitate copy-paste into spreadsheets.
+
+        Args:
+            file: Which IO stream to print to. Do not use stdout, as tab separator is not preserved.
+
+        Returns:
+            None
+        """
+        combined_df = self.to_dataframe()
+
+        # Filter out some columns and rows for better readability when printing
+        filtered_column_df = combined_df.drop(columns=EXCLUDED_COLUMNS_WHEN_PRINTING)
+        for filter_name in EXCLUDED_EVENTS_WHEN_PRINTING:
+            filtered_column_df = filtered_column_df[
+                ~filtered_column_df["event_name"].str.contains(filter_name)
+            ]
+        filtered_column_df.reset_index(drop=True, inplace=True)
+
+        filtered_column_df.to_csv(file, sep="\t")
+
+
     # TODO: write unit test
     def find_total_for_module(self, module_name: str) -> float:
         """

devtools/inspector/inspector_cli.py

@@ -43,6 +43,11 @@ def main() -> None:
         required=False,
         help="Provide an optional buffer file path.",
     )
+    parser.add_argument(  
+        "--csv_path",
+        required=False,
+        help="Provide an optional csv file path.",
+    )
     parser.add_argument("--compare_results", action="store_true")
 
     args = parser.parse_args()
@@ -55,6 +60,8 @@ def main() -> None:
         target_time_scale=TimeScale(args.target_time_scale),
     )
     inspector.print_data_tabular()
+    if args.csv_path:
+        inspector.save_data_to_csv(args.csv_path)
     if args.compare_results:
         for event_block in inspector.event_blocks:
             if event_block.name == "Execute":