old_contents: def login(registry, user, pwd, email):
    log = logging.getLogger("dcb.login")
    if pwd is not None:
      log.info("logging {0} into {1}...".format(user, registry))
      check_call(['docker',
                  'login',
                  '-u', user,
                  '-p', pwd,
                  '-e', email,
                  registry])
    else:
      log.info("no password specified for {0}. not logging in.".format(user))
      
  
new_contents: import logging
  from subprocess import check_call
  
  def login(registry, user, pwd, email):
    log = logging.getLogger("dcb.login")
    if pwd is not None:
      log.info("logging {0} into {1}...".format(user, registry))
      check_call(['docker',
                  'login',
                  '-u', user,
                  '-p', pwd,
                  '-e', email,
                  registry])
    else:
      log.info("no password specified for {0}. not logging in.".format(user))
      
  
subject: fix imports