from fastavro import writer, parse_schema

# 1. Define the schema
schema = {
    'doc': 'name',
    'name': 'name',
    'namespace': 'name',
    'type': 'record',
    'fields': [
        {'name': 'a', 'type': 'float'},
        {'name': 'b', 'type': 'string'},
        ...
    ]
}
parsed_schema = parse_schema(schema)

# 2. Convert pd.DataFrame to records - list of dictionaries
records = df.to_dict('records')

# 3. Write to Avro file
with open('file_name.avro', 'wb') as out:
    writer(out, parsed_schema, records)