code: def poisson(y_true, y_pred):
      y_true = ivy.astype(y_true, y_pred.dtype, copy=False)
      return ivy.mean(y_pred - y_true * ivy.log(y_pred + 1e-7), axis=-1)
  
imports: import ivy
  from ivy.functional.frontends.tensorflow.func_wrapper import to_ivy_arrays_and_back
label_desc: Use image node_id 18 for calling a global function with example usage: poisson(y_true, y_pred) and returns: ivy