code: def _packb2(obj, **options):
      
      fp = io.BytesIO()
      _pack2(obj, fp, **options)
      return fp.getvalue()
docs: Serialize a Python object into MessagePack bytes.
  
      Args:
          obj: a Python object
  
      Kwargs:
          ext_handlers (dict): dictionary of Ext handlers, mapping a custom type
                               to a callable that packs an instance of the type
                               into an Ext object
          force_float_precision (str): "single" to force packing floats as
                                       IEEE-754 single-precision floats,
                                       "double" to force packing floats as
                                       IEEE-754 double-precision floats.
  
      Returns:
          A 'str' containing serialized MessagePack bytes.
  
      Raises:
          UnsupportedType(PackException):
              Object type not supported for packing.
  
      Example:
      >>> umsgpack.packb({u"compact": True, u"schema": 0})
      '\x82\xa7compact\xc3\xa6schema\x00'
      >>>