code: def test_shared_axis_categorical():
      # str uses category.StrCategoryConverter
      d1 = {"a": 1, "b": 2}
      d2 = {"a": 3, "b": 4}
      fig, (ax1, ax2) = plt.subplots(1, 2, sharex=True, sharey=True)
      ax1.plot(d1.keys(), d1.values())
      ax2.plot(d2.keys(), d2.values())
      ax1.xaxis.set_units(UnitData(["c", "d"]))
      assert "c" in ax2.xaxis.get_units()._mapping.keys()
  
imports: from datetime import datetime, timezone, timedelta
  import platform
  from unittest.mock import MagicMock
  import matplotlib.pyplot
  from matplotlib.testing.decorators import check_figures_equal, image_comparison
  import matplotlib.units
  from matplotlib.category import UnitData
  import numpy
  import pytest
label_desc: Use image node_id 13 for calling a global function with example usage: test_shared_axis_categorical() without return types