class_docstr: A casting version of the byte memory view trait.
code: def validate(self, obj, value):
      if isinstance(value, memoryview) and value.format == "B":
          return value
  
      try:
          mv = memoryview(value)
          if mv.format != "B":
              mv = mv.cast("B")
          return mv
      except Exception:
          self.error(obj, value)
  
imports: import re
  import traitlets
  import datetime
label_desc: Use image node_id 1 for calling the CByteMemoryView obj's underlying member method code with example usage: obj.validate(obj, value) and returns: value, mv