code: def test_for_each_trace_lowercase_names(self):
      # Names are all uppercase to start
      original_names = [t.name for t in self.fig.data]
      self.assertTrue([str.isupper(n) for n in original_names])
  
      # Lower case names
      result_fig = self.fig.for_each_trace(
          lambda t: t.update(name=t.name.lower())
      )
  
      # Check chaning
      self.assertIs(result_fig, self.fig)
  
      # Check that names were altered
      self.assertTrue(
          all(
              [
                  t.name == n.lower()
                  for t, n in zip(result_fig.data, original_names)
              ]
          )
      )
  
imports: from unittest import TestCase
  import inspect
  import copy
  import pytest
  import plotly.graph_objs
  from plotly.subplots import make_subplots
  from functools import reduce
label_desc: Use image node_id 10 for calling the TestSelectForEachUpdateTraces obj's underlying member method code with example usage: obj.test_for_each_trace_lowercase_names() without return types