code: def write_deltas(self, f, numbers):
      return self.write_nums(f, list(delta_encode(numbers)))
  
imports: from array import array
  from whoosh.compat import xrange
  from whoosh.system import emptybytes
  from whoosh.system import pack_byte, unpack_byte
  from whoosh.system import pack_ushort_le, unpack_ushort_le
  from whoosh.system import pack_uint_le, unpack_uint_le
label_desc: Use image node_id 3 for calling the NumberEncoding obj's underlying member method code with example usage: obj.write_deltas(f, numbers) and returns: self