code: def equality_cases():
      pairs = [
          [pipeline_first(), pipeline_first()],
          [pipeline_third(), pipeline_third()],
          [pipeline_fourth(), pipeline_fourth()],
      ]
  
      # the following changes don't affect to pipelines equality:
      for node_num, type in enumerate(["knn", "lda"]):
          pairs[1][1].root_node.nodes_from[
              node_num
          ].operation.operation_type = type
  
      for node_num in ((2, 1), (1, 2)):
          old_node = pairs[2][1].root_node.nodes_from[node_num[0]]
          new_node = deepcopy(
              pairs[2][0].root_node.nodes_from[node_num[1]]
          )
          pairs[2][1].update_subtree(old_node, new_node)
  
      return pairs
  
file_path: FEDOT/test/unit/pipelines/test_pipeline_comparison.py
imports: import itertools
  from copy import deepcopy
  import pytest
  from fedot.core.pipelines.node import PipelineNode
  from fedot.core.pipelines.pipeline import Pipeline
label_desc: Use image node_id 5 for calling a global function with example usage: equality_cases() and returns: pairs