class_docstr: DGL context strucure.
docstr: Whether this device exist.
docstr_tok: ["Whether","this","device","exist","."]
code: def exist(self):
      """Whether this device exist."""
      return (
          _api_internal._GetDeviceAttr(
              self.device_type, self.device_id, 0
          )
          != 0
      )
  
imports: from __future__ import absolute_import
  import ctypes
  import json
  import numpy
  from ..None import _api_internal
  from .base import _LIB, check_call
label_desc: Use image node_id 3 for calling the DGLContext obj's underlying member method code with example usage: obj.exist() and returns: unknown