title: Set all markers to the same fixed size in Plotly Express scatterplot
body: <p>I'm looking for a way to set all markers in a Plotly Express scatter plot to the same size. <br>
  I want to specify that fixed size myself.</p>
  <p>I know you can use a variable to set as size of the markers (with <code>px.scatter(size='column_name')</code>, but then they get all different sizes. They all need to have the same size.</p>
  <p>Here's my sample code:</p>
  <pre><code>import pandas as pd
  import plotly.express as px
  
  df = pd.DataFrame({
      'colA': np.random.rand(10),
      'colB': np.random.rand(10),
  })
  
  fig = px.scatter(
      df, 
      x='colA', 
      y='colB', 
  )
  </code></pre>
  <p><a href="https://i.stack.imgur.com/tPyxum.png" rel="noreferrer"><img src="https://i.stack.imgur.com/tPyxum.png" alt="plotly express how to give markers all same fixed size" /></a></p>