tains a specification of how the value should be
presented, including such details as field width, alignment, padding, decimal
precision and so on.  Each value type can define its own “formatting
mini-language” or interpretation of the <em>format_spec</em>.</p>
<p>Most built-in types support a common formatting mini-language, which is
described in the next section.</p>
<p>A <em>format_spec</em> field can also include nested replacement fields in certain
positions within it. These nested replacement fiel