code: def _is_expr(arg):
      return isinstance(arg, (foe.ViewExpression, dict))
  
imports: import itertools
  import warnings
  import numpy
  import sklearn.linear_model
  import sklearn.metrics
  import eta.core.serial
  import eta.core.utils
  import fiftyone.core.expressions
  import fiftyone.core.labels
label_desc: Use image node_id 5 for calling a global function with example usage: _is_expr(arg) and returns: isinstance