class_docstr: list of beams at specific time-step
code: def dump(self):
      for k in self.beams.keys():
          print(str(self.beams[k]).encode("ascii", "replace"))
  
imports: from __future__ import division
  from __future__ import print_function
  import copy
label_desc: Use image node_id 6 for calling the BeamList obj's underlying member method code with example usage: obj.dump() without return types