title: How do I programmatically create a button and assign a macro to it upon opening spreadsheet?
body: <p>I need upon opening a spreadsheet to produce a button and automatically assign a macro I previously created. Let's call this macro "edit_colour".</p>
  
  <p>I know how to execute a MsgBox with "Hello World" using the following,</p>
  
  <pre><code>Private Sub Workbook_Open()
  MsgBox "Hello World"
  End Sub
  </code></pre>