Update guide/src/parallelism.md

Co-authored-by: Yuji Kanagawa <[email protected]>

Author: davidhewitt

guide/src/parallelism.md

@@ -2,7 +2,7 @@
 
 CPython has the infamous [Global Interpreter Lock](https://docs.python.org/3/glossary.html#term-global-interpreter-lock), which prevents several threads from executing Python bytecode in parallel. This makes threading in Python a bad fit for [CPU-bound](https://stackoverflow.com/questions/868568/) tasks and often forces developers to accept the overhead of multiprocessing.
 
-In PyO3 parallelism can be easily achieved in Rust-only code. Let's take a look at our [word-count](https://github.com/PyO3/pyo3/blob/main/examples/word-count/src/lib.rs) example, where we have a `search` function that utilizes the [rayon](https://github.com/nikomatsakis/rayon) crate to count words in parallel.
+In PyO3 parallelism can be easily achieved in Rust-only code. Let's take a look at our [word-count](https://github.com/PyO3/pyo3/blob/main/examples/word-count/src/lib.rs) example, where we have a `search` function that utilizes the [rayon](https://github.com/rayon-rs/rayon) crate to count words in parallel.
 ```rust, ignore
 #[pyfunction]
 fn search(contents: &str, needle: &str) -> usize {