make pip ignore an existing wheel : <p>If a <code>.whl</code> is available online, <code>pip</code> always installs it rather than compiling from source. However, for some specific module, the wheel happened to be compiled for the next processor generation and doesn't run on a specific machine.</p>

<p>If I command it to just download the package, then it still downloads the wheel rather than source. Does <code>pip</code> have some mechanism to override this preference?</p>
