code: def test_labels():
      tips = px.data.tips()
      fig = px.scatter(
          tips,
          x="total_bill",
          y="tip",
          facet_row="time",
          facet_col="day",
          color="size",
          symbol="sex",
          labels={c: c.upper() for c in tips.columns},
      )
      assert "SEX" in fig.data[0].hovertemplate
      assert "TOTAL_BILL" in fig.data[0].hovertemplate
      assert "SIZE" in fig.data[0].hovertemplate
      assert "DAY" in fig.data[0].hovertemplate
      assert "TIME" in fig.data[0].hovertemplate
      assert fig.layout.legend.title.text.startswith("SEX")
      assert fig.layout.xaxis.title.text == "TOTAL_BILL"
      assert fig.layout.coloraxis.colorbar.title.text == "SIZE"
      assert fig.layout.annotations[0].text.startswith("DAY")
      assert fig.layout.annotations[4].text.startswith("TIME")
  
file_path: plotly.py/packages/python/plotly/plotly/tests/test_optional/test_px/test_px.py
imports: import plotly.express
  import plotly.io
  import numpy
  import pytest
  from itertools import permutations
label_desc: Use image node_id 3 for calling a global function with example usage: test_labels() without return types