### Pydantic v1

**This version of FastAPI still supports Pydantic v1**. And although Pydantic v1 will be deprecated at some point, it will still be supported for a while.

<code>int</code>; for arrays or constant strings, constant indices must also be in range.
If both indices are constant, they must satisfy <code>low &lt;= high</code>.
If the indices are out of range at run time, a <a href="#Run_time_panics">run-time panic</a> occurs.
</p>

<p>
Except for <a href="#Constants">untyped strings</a>, if the sliced operand is a string or slice,