Function parse_headers 

pub fn parse_headers<'a, I>(headers: I) -> Option<SentryTrace>
where
    I: IntoIterator<Item = (&'a str, &'a str)>,

👎Deprecated:

use TracePropagationContext::try_from_headers instead

Extracts distributed tracing metadata from headers (or, generally, key-value pairs), considering the values for sentry-trace.