code: def _get_context(keyspaces, connections):
      
  
      if keyspaces:
          if not isinstance(keyspaces, (list, tuple)):
              raise ValueError('keyspaces must be a list or a tuple.')
  
      if connections:
          if not isinstance(connections, (list, tuple)):
              raise ValueError('connections must be a list or a tuple.')
  
      keyspaces = keyspaces if keyspaces else [None]
      connections = connections if connections else [None]
  
      return product(connections, keyspaces)
docs: Return all the execution contexts