def _get_code(data, position, obj_end, opts, element_name):
 (code, position) = _get_string(data, position, obj_end, opts, element_name)
 return (Code(code), position)

def _get_code ( data , position , obj_end , opts , element_name ) : ( code , position ) = _get_string ( data , position , obj_end , opts , element_name ) return ( Code ( code ) , position )
decode a bson code to bson .