old_contents: #!/usr/bin/python3
  
  from checker.abstract import AbstractChecker
  
  import base64
  import sys
  import codecs
  
  class ContestChecker(AbstractChecker):
      def __init__(self, tick, team, service, ip):
          AbstractChecker.__init__(self, tick, team, service, ip)
  
      def _rpc(self, function, *args):
          sys.stdout.write("%s %s\n" % (function, " ".join(args)))
          sys.stdout.flush()
          return sys.stdin.readline().strip()
  
      def get_flag(self, tick, payload=None):
          if payload is None:
              return self._rpc("FLAG", str(tick))
          else:
              payload = codecs.encode(payload, 'hex').decode('latin-1')
              return self._rpc("FLAG", str(tick), payload)
  
      def store_blob(self, ident, blob):
          data = base64.b64encode(blob)
          return self._rpc("STORE", ident, base64.b64encode(data).decode('latin-1'))
  
      def retrieve_blob(self, ident):
          data = self._rpc("RETRIEVE", ident)
          return base64.b64decode(data)
  
new_contents: #!/usr/bin/python3
  
  from checker.abstract import AbstractChecker
  
  import base64
  import sys
  import codecs
  
  class ContestChecker(AbstractChecker):
      def __init__(self, tick, team, service, ip):
          AbstractChecker.__init__(self, tick, team, service, ip)
  
      def _rpc(self, function, *args):
          sys.stdout.write("%s %s\n" % (function, " ".join(args)))
          sys.stdout.flush()
          return sys.stdin.readline().strip()
  
      def get_flag(self, tick, payload=None):
          if payload is None:
              return self._rpc("FLAG", str(tick))
          else:
              payload = codecs.encode(payload, 'hex').decode('latin-1')
              return self._rpc("FLAG", str(tick), payload)
  
      def store_blob(self, ident, blob):
          data = base64.b64encode(blob)
          return self._rpc("STORE", ident, data.decode('latin-1'))
  
      def retrieve_blob(self, ident):
          data = self._rpc("RETRIEVE", ident)
          return base64.b64decode(data)
  
subject: Fix double-encoding of binary blobs