code: def encodeDeltaRunAsZeroes_(deltas, offset, bytearr):
      pos = offset
      numDeltas = len(deltas)
      while pos < numDeltas and deltas[pos] == 0:
          pos += 1
      runLength = pos - offset
      while runLength >= 64:
          bytearr.append(DELTAS_ARE_ZERO | 63)
          runLength -= 64
      if runLength:
          bytearr.append(DELTAS_ARE_ZERO | (runLength - 1))
      return pos
  
imports: from fontTools.misc.fixedTools import fixedToFloat, floatToFixed, floatToFixedToStr, strToFixedToFloat, otRound
  from fontTools.misc.textTools import safeEval
  import array
  from collections import Counter, defaultdict
  import io
  import logging
  import struct
  import sys
label_desc: Use image node_id 16 for calling the TupleVariation obj's underlying member method code with example usage: obj.encodeDeltaRunAsZeroes_(deltas, offset, bytearr) and returns: pos