title: Plotly: How to color the fill between two lines based on a condition?
body: <p>I want to add a fill colour between the black and blue line on my Plotly chart. I am aware this can be accomplished already with Plotly but I am not sure how to fill the chart with two colours based on conditions.<a href="https://i.stack.imgur.com/vC9ZQ.png" rel="noreferrer"><img src="https://i.stack.imgur.com/vC9ZQ.png" alt="This is my Plotly chart" /></a><a href="https://i.stack.imgur.com/m9AyQ.png" rel="noreferrer"><img src="https://i.stack.imgur.com/m9AyQ.png" alt="This is what I want to achieve" /></a></p>
  <p>The chart with the blue background is my Plotly chart. I want to make it look like the chart with the white background. (Ignore the red and green bars on the white chart)</p>
  <p>The conditions I want it to pass is:</p>
  <p>Fill the area between the two lines GREEN, if the black line is above the blue line.</p>
  <p>Fill the area between the two lines RED, if the black line is below the blue line.</p>
  <p>How can this be done with Plotly? If this is not possible with Plotly can it be accomplished with other graphing tools that work with Python.</p>