code: def _full_slicer_len(full_slicer):
      """Return length of slicer processed by ``fill_slicer``"""
      start, stop, step = (
          full_slicer.start,
          full_slicer.stop,
          full_slicer.step,
      )
      if stop is None:  # case of negative step
          stop = -1
      gap = stop - start
      if (step > 0 and gap <= 0) or (step < 0 and gap >= 0):
          return 0
      return int(np.ceil(gap / step))
  
imports: import operator
  from functools import reduce
  from mmap import mmap
  from numbers import Integral
  import numpy
label_desc: Use image node_id 5 for calling a global function with example usage: _full_slicer_len(full_slicer) and returns: int, int