Update README.md
Corrected grammatical error.
@@ -104,7 +104,7 @@ cargo build --release --target wasm32-wasi --features="freeze-stdlib"
### JIT (Just in time) compiler
-RustPython has an **very** experimental JIT compiler that compile python functions into native code.
+RustPython has a **very** experimental JIT compiler that compile python functions into native code.
#### Building
