Write an AVRO file

Below, I provide some Python code to write an AVRO file. An AVRO file consists of a scheme and a set of records. The records are written in binary format. The scheme is as follows:

{"type": "record",
 "name": "StringPair",
 "doc": "A pair of strings.",
 "fields": [
     {"name": "left", "type": "string"},
     {"name": "right", "type": "string"}]}

The code to write such file is as follows:

import sys
from avro import schema
from avro import io
from avro import datafile
if __name__ == '__main__':
    if len(sys.argv) != 2:
            sys.exit('Usage: %s ' % sys.argv[0])
avro_file = sys.argv[1]
writer = open(avro_file, 'wb')
datum_writer = io.DatumWriter()
schema_object = schema.Parse(open(b'C:\\Users\\tmaanen\\.spyder-py3\\tom.avsc', "r").read())
dfw = datafile.DataFileWriter(writer, datum_writer, schema_object)
for line in sys.stdin.readlines():
    (left, right) = line.split(',')
    dfw.append({'left':left, 'right':right});
dfw.close()

The script can be run on the command line as C:\ProgramData\Anaconda3\python.exe C:\Users\tmaanen\.spyder-py3\TomHdfs.py C:\Users\tmaanen\.spyder-py3\a.avro