code: def memzero(m):
      try:
          m[:] = 0
      except IndexError:  # cffi buffer
          m[0 : len(m)] = b"\0" * len(m)
  
imports: from mpi4py import MPI
  import mpiunittest
  import sys
label_desc: Use image node_id 1 for calling a global function with example usage: memzero(m) without return types