I’m not familiar with the syntax highlighting system / settings as a whole, but if you just want to get rid of the red text you could use CSS in your site’s theme:
code.language-python span {
color: inherit;
}
The red is used for indicating strings, so if you wanted to just change that to a different color you could do something like this:
code.language-python span.hljs-string {
color: #FFF; /* Replace with intended color */
}
Aside from the red text, were there other parts that are being mis-formatted?