I used both fastparquet and pyarrow for converting protobuf data to parquet and to query the same in S3 using Athena. Both worked, however, in my use-case, which is a lambda function, package zip file has to be lightweight, so went ahead with fastparquet. (fastparquet library was only about 1.1mb, while pyarrow library was 176mb, and Lambda package limit is 250mb).
I used the following to store a dataframe as parquet file:
from fastparquet import write
parquet_file = path.join(filename + '.parq')
write(parquet_file, df_data)