old_contents: import os
  from urllib.request import urlretrieve
  
  
  def fetch(filename, destination_path,
            aws_bucket='serenata-de-amor-data',
            aws_region='s3-sa-east-1'):
      url = 'https://{}.amazonaws.com/{}/{}'.format(aws_region,
                                                    aws_bucket,
                                                    filename)
      filepath = os.path.join(destination_path, filename)
      if not os.path.exists(filepath):
          urlretrieve(url, filepath)
  
  
  def fetch_latest_backup(destination_path,
                          aws_bucket='serenata-de-amor-data',
                          aws_region='s3-sa-east-1'):
      files = (
          '2016-08-08-ceap-datasets.md',
          '2016-08-08-current-year.xz',
          '2016-08-08-datasets-format.html',
          '2016-08-08-last-year.xz',
          '2016-08-08-previous-years.xz',
          '2016-09-03-companies.xz',
          '2016-11-11-congressperson-relatives.xz',
          '2016-11-19-current-year.xz',
          '2016-11-19-last-year.xz',
          '2016-11-19-previous-years.xz',
          '2016-11-19-reimbursements.xz',
          '2016-11-28-congressperson-civil-names.xz',
          '2016-11-29-yelp-companies.xz',
          '2016-12-02-foursquare-companies.xz',
          '2016-12-15-speeches.xz',
          '2016-12-20-impeded-non-profit-entities.xz',
          '2016-12-21-deputies.xz',
          '2016-12-21-inident-and-suspended-companies.xz',
          '2016-12-21-national-register-punished-companies.xz',
          '2016-12-21-presences.xz',
          '2016-12-21-sessions.xz',
          '2016-12-21-speeches.xz',
          '2016-12-22-agreements.xz',
          '2016-12-22-amendments.xz'
      )
      for filename in files:
          fetch(filename, destination_path, aws_bucket, aws_region)
  
new_contents: import os
  from urllib.request import urlretrieve
  
  
  def fetch(filename, destination_path,
            aws_bucket='serenata-de-amor-data',
            aws_region='s3-sa-east-1'):
      url = 'https://{}.amazonaws.com/{}/{}'.format(aws_region,
                                                    aws_bucket,
                                                    filename)
      filepath = os.path.join(destination_path, filename)
      if not os.path.exists(filepath):
          urlretrieve(url, filepath)
  
  
  def fetch_latest_backup(destination_path,
                          aws_bucket='serenata-de-amor-data',
                          aws_region='s3-sa-east-1'):
      files = (
          '2016-08-08-ceap-datasets.md',
          '2016-08-08-current-year.xz',
          '2016-08-08-datasets-format.html',
          '2016-08-08-last-year.xz',
          '2016-08-08-previous-years.xz',
          '2016-09-03-companies.xz',
          '2016-11-11-congressperson-relatives.xz',
          '2016-11-19-current-year.xz',
          '2016-11-19-last-year.xz',
          '2016-11-19-previous-years.xz',
          '2016-11-19-reimbursements.xz',
          '2016-11-28-congressperson-civil-names.xz',
          '2016-11-29-yelp-companies.xz',
          '2016-12-02-foursquare-companies.xz',
          '2016-12-15-speeches.xz',
          '2016-12-20-impeded-non-profit-entities.xz',
          '2016-12-21-deputies.xz',
          '2016-12-21-inident-and-suspended-companies.xz',
          '2016-12-21-national-register-punished-companies.xz',
          '2016-12-21-presences.xz',
          '2016-12-21-sessions.xz',
          '2016-12-21-speeches.xz',
          '2016-12-22-agreements.xz',
          '2016-12-22-amendments.xz',
          '2017-03-20-purchase-suppliers.xz'
      )
      for filename in files:
          fetch(filename, destination_path, aws_bucket, aws_region)
  
subject: Add purchase suppliers dataset