title: Specify read buffer size when reading from Google Cloud Storage
body: <p>I am trying open a file I have in Google Cloud Storage using cloudstorage library. 
  I get the error that module cloudstorage has no attribute 'open'. </p>
  
  <p>I want to specify a read buffer size when I load the file from Google Cloud Storage to Google BigQuery. This is the function that I wish to use for that. The parameters require a file like object. </p>
  
  <pre><code>Client.load_table_from_file(file_obj, destination, rewind=False, size=None, num_retries=6, job_id=None, job_id_prefix=None, location=None, project=None, job_config=None)[source]
  </code></pre>
  
  <p>Upload the contents of this table from a file-like object.</p>
  
  <p>Is there any other way to the pass the Cloud Storage file as an object to this method? Or perhaps another way to load a file from cloud storage to Google BigQuery while specifying a read buffer size.</p>
  
  <pre><code> from google.cloud import bigquery
   from google.cloud import storage 
   import cloudstorage as gcs
   def hello_gcs(event, context):
      gcs_file = gcs.open('no-trigger/transaction.csv')
      job_config = bigquery.LoadJobConfig()
      job_config.autodetect = False
      job_config.max_bad_records=1
      job_config.create_disposition = 'CREATE_IF_NEEDED'
      job_config.source_format = bigquery.SourceFormat.CSV
      load_job = bclient.load_table_from_file(
      gcs_file,
      dataset_ref.table(temptablename),
      location='asia-northeast1',
      size=2147483648,
      job_config=job_config)  # API request
  </code></pre>