Add comment and release note

Author: bnaul

doc/source/whatsnew/v1.0.0.rst

@@ -205,6 +205,7 @@ I/O
 - Improve infinity parsing. :meth:`read_csv` now interprets ``Infinity``, ``+Infinity``, ``-Infinity`` as floating point values (:issue:`10065`)
 - Bug in :meth:`DataFrame.to_csv` where values were truncated when the length of ``na_rep`` was shorter than the text input data. (:issue:`25099`)
 - Bug in :func:`DataFrame.to_string` where values were truncated using display options instead of outputting the full content (:issue:`9784`)
+- Bug in :func:`DataFrame.to_parquet` where writing to GCS would fail with `engine='fastparquet'` if the file did not already exist (:issue:`28326`)
 
 Plotting
 ^^^^^^^^

pandas/io/parquet.py

@@ -160,11 +160,11 @@ def write(
             kwargs["file_scheme"] = "hive"
 
         if is_s3_url(path) or is_gcs_url(path):
-            # path is s3:// so we need to open the s3file in 'wb' mode.
+            # if path is s3:// or gs:// we need to open the file in 'wb' mode.
             # TODO: Support 'ab'
 
             path, _, _, _ = get_filepath_or_buffer(path, mode="wb")
-            # And pass the opened s3file to the fastparquet internal impl.
+            # And pass the opened file to the fastparquet internal impl.
             kwargs["open_with"] = lambda path, _: path
         else:
             path, _, _, _ = get_filepath_or_buffer(path)