class="code">(<span class="string">"%4d"</span>,&nbsp;1234)</code>.
      This behaviour is not mere format substitution, since the conversion
      returns the format string read as additional argument. If you need
      pure format substitution, use special flag <code class="code">_</code> to discard the
      extraneous argument: conversion <code class="code">%_(&nbsp;fmt&nbsp;%)</code> reads a format string
      <code class="code">rf</code> and then behaves the same as format string <code class="code">