px.timeline Incorrectly interprets x_end datetimes

The px.timeline function incorrectly generates the end times of the bar traces. The end times are placed before the start times.

Python version 3.8.6
Plotly version 5.4

Steps to reproduce:

import datetime
import plotly.express as px
t0 = datetime.datetime.now()
tf = t0 + datetime.timedelta(hours=1)
px.timeline(x_start=[t0], x_end=[tf])

print(t0)
print(tf)

Produces

2021-11-16 12:21:14.800827  # t0
2021-11-16 13:21:14.800827  # tf

The resulting figure is below. Notice that the right edge of the bar is the same as the start time, but the left edge of the bar is something else entirely.

The behavior is the same when passing a dataframe and column names. If you generate a scatter plot using the same datetime objects, the output works as expected (shown below).

从 px.timeline 入口点开始，使用报告中显示的 datetime 值重现该问题，并将其 bar trace 的坐标与使用相同值的散点图进行比较。跟踪 x_start 和 x_end 如何转换到 figure 中，然后验证生成的 bar 是否具有预期的开始和结束时间，以及 dataframe-and-column-names 情况是否也能正确运行。