class_docstr: Abstract base class for objects that can be used to compose an SQL string.
  
  `!Composable` objects can be passed directly to `~cursor.execute()`,
  `~cursor.executemany()`, `~cursor.copy_expert()` in place of the query
  string.
  
  `!Composable` objects can be joined using the ``+`` operator: the result
  will be a `Composed` instance containing the objects joined. The operator
  ``*`` is also supported with an integer argument: the result is a
  `!Composed` instance containing the left argument repeated as many times as
  requested.
code: def __add__(self, other):
      if isinstance(other, Composed):
          return Composed([self]) + other
      if isinstance(other, Composable):
          return Composed([self]) + Composed([other])
      else:
          return NotImplemented
  
imports: import string
  from psycopg2 import extensions
label_desc: Use image node_id 4 for calling the Composable obj's underlying member method code with example usage: obj.__add__(other) and returns: unknown, unknown, NotImplemented