class_docstr: Backend storage for our "array of bits" using a file in which we seek
class_docstr_tok: ["Backend","storage","for","our","``","array","of","bits","''","using","a","file","in","which","we","seek"]
docstr: Return true iff bit number bitno is set
code: def is_set(self, bitno):
      """Return true iff bit number bitno is set"""
      byteno, bit_within_wordno = divmod(bitno, 8)
      mask = 1 << bit_within_wordno
      os.lseek(self.file_, byteno, os.SEEK_SET)
      byte = os.read(self.file_, 1)[0]
      return byte & mask
  
imports: import array
  import math
  import os
  import random
label_desc: Use image node_id 2 for calling the File_seek_backend obj's underlying member method code with example usage: obj.is_set(bitno) and returns: unknown