code: def test_pandas_time_series_date_formatter(self):
      ndays = 3
      x = pd.date_range("1/1/2001", periods=ndays, freq="D")
      y = [random.randint(0, 10) for i in range(ndays)]
      s = pd.DataFrame(y, columns=["a"])
  
      s["Date"] = x
      s.plot(x="Date")
  
      fig = plt.gcf()
      pfig = tls.mpl_to_plotly(fig)
  
      expected_x = (
          "2001-01-01 00:00:00",
          "2001-01-02 00:00:00",
          "2001-01-03 00:00:00",
      )
      expected_x0 = 11323.0  # this is floating point days since epoch
  
      x0 = fig.axes[0].lines[0].get_xydata()[0][0]
      self.assertEqual(x0, expected_x0)
      self.assertEqual(pfig["data"][0]["x"], expected_x)
  
file_path: plotly.py/packages/python/plotly/plotly/tests/test_optional/test_matplotlylib/test_date_times.py
imports: import datetime
  import random
  from unittest import TestCase
  import pytest
  import pandas
  import plotly.tools
  from plotly import optional_imports
label_desc: Use image node_id 2 for calling the TestDateTimes obj's underlying member method code with example usage: obj.test_pandas_time_series_date_formatter() without return types