code: def column_families(keyspace=None):
      '''
      Return existing column families for all keyspaces
      or just the provided one.
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' cassandra.column_families
          salt '*' cassandra.column_families <keyspace>
      '''
      sys = _sys_mgr()
      ksps = sys.list_keyspaces()
  
      if keyspace:
          if keyspace in ksps:
              return list(sys.get_keyspace_column_families(keyspace).keys())
          else:
              return None
      else:
          ret = {}
          for kspace in ksps:
              ret[kspace] = list(sys.get_keyspace_column_families(kspace).keys())
  
          return ref column_families(keyspace=None):
      '''
      Return existing column families for all keyspaces
      or just the provided one.
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' cassandra.column_families
          salt '*' cassandra.column_families <keyspace>
      '''
      sys = _sys_mgr()
      ksps = sys.list_keyspaces()
  
      if keyspace:
          if keyspace in ksps:
              return list(sys.get_keyspace_column_families(keyspace).keys())
          else:
              return None
      else:
          ret = {}
          for kspace in ksps:
              ret[kspace] = list(sys.get_keyspace_column_families(kspace).keys())
  
          return ret
docs: Return existing column families for all keyspaces
      or just the provided one.
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' cassandra.column_families
          salt '*' cassandra.column_families <keyspace>