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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def PrettyPrinter(obj):
 """Pretty printers for AppEngine objects."""


  if ndb and isinstance(obj, ndb.Model):
    return six.iteritems(obj.to_dict()), 'ndb.Model(%s)' % type(obj).__name__

  if messages and isinstance(obj, messages.Enum):
    return [('name', obj.name), ('number', obj.number)], type(obj).__name__

  return None