code: def pad(data, size):
      r"""Pad byte string 'data' with null bytes until its length is a
      multiple of 'size'.
  
      >>> len(pad(b'abcd', 4))
      4
      >>> len(pad(b'abcde', 2))
      6
      >>> len(pad(b'abcde', 4))
      8
      >>> pad(b'abcdef', 4) == b'abcdef\x00\x00'
      True
      """
      data = tobytes(data)
      if size > 1:
          remainder = len(data) % size
          if remainder:
              data += b"\0" * (size - remainder)
      return data
  
imports: import ast
  import string
label_desc: Use image node_id 7 for calling a global function with example usage: pad(data, size) and returns: data