code: def my_subtract(first, second):
      return first - second
  
file_path: haystack/test/core/sample_components/test_accumulate.py
imports: from haystack.testing.sample_components.accumulate import Accumulate, _default_function
label_desc: Use image node_id 1 for calling a global function with example usage: my_subtract(first, second) and returns: unknown