title: Style for continued multi-line f-strings
body: <p>Do any popular Python style guides express a preference between:</p>
  
  <pre><code>x = (f'One plus one is '
       f'equal to {1+1}')
  </code></pre>
  
  <p>and:</p>
  
  <pre><code>x = ('One plus one is '
       f'equal to {1+1}')
  </code></pre>
  
  <p>Does it make sense to omit the <code>f</code> prefix for lines that don't involve interpolation? Should it be included for consistency? </p>