Documentation PR

• [Y ] I'veseen thedoc/README.md file
• [ Yes, it runs on 5.24.1 ] This change runs in the current version of Plotly on PyPI and targets thedoc-prod branch OR it targets themaster branch
• [ Yes, it is PX ] If this PR modifies the first example in a page or adds a new one, it is apx example if at all possible
• [ Y ] Every new/modified example has a descriptive title and motivating sentence or paragraph
• [ Y ] Every new/modified example is independently runnable
• [ Y ] Every new/modified example is optimized for short line countand focuses on the Plotly/visualization-related aspects of the example rather than the computation required to produce the data being visualized
• [ made up, but relatable ] Meaningful/relatable datasets are used for all new examples instead of randomly-generated data where possible
• [ N/A ] The random seed is set if using randomly-generated data in new/modified examples
• [ on our to-do list ] New/modified remote datasets are loaded fromhttps://plotly.github.io/datasets and added tohttps://github.com/plotly/datasets
• [ Y ] Large computations are avoided in the new/modified examples in favour of loading remote datasets that represent the output of such computations
• [ Y ] Imports areplotly.graph_objects as go /plotly.express as px /plotly.io as pio
• [ Y ] Data frames are always calleddf
• [ Y ]fig = <something> call is high up in each new/modified example (eitherpx.<something> ormake_subplots orgo.Figure)
• [ Y ] Liberal use is made offig.add_* andfig.update_* rather thango.Figure(data=..., layout=...) in every new/modified example
• [ Y ] Specific adders and updaters likefig.add_shape andfig.update_xaxes are used instead of bigfig.update_layout calls in every new/modified example
• [ Y ]fig.show() is at the end of each new/modified example
• [ Y ]plotly.plot() andplotly.iplot() are not used in any new/modified example
• [ Y ] Hex codes for colors are not used in any new/modified example in favour ofthese nice ones

Code PR

• I have read through thecontributing notes and understand the structure of the package. In particular, if my PR modifies code ofplotly.graph_objects, my modifications concern thecodegen files and not generated files.
• I have added tests (if submitting a new feature or correcting a bug) or
  modified existing tests.
• For a new feature, I have added documentation examples in an existing or
  new tutorial notebook (please see the doc checklist as well).
• I have added a CHANGELOG entry if fixing/changing/adding anything substantial.
• For a new feature or a change in behaviour, I have updated the relevant docstrings in the code to describe the feature or behaviour (please see the doc checklist as well).

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