Running Python in Rust example in README errors

[haydonryan]

Bug Description

Sample fails to compile for calling python in rust

Brand new to trying to run python in a rust app haven't found one sample that compiles yet.

Steps to Reproduce

1. Cargo new python test.
2. add py03 to Cargo.toml:

$ cat Cargo.toml 
[package]
name = "pytest"
version = "0.1.0"
edition = "2021"

[dependencies]

[dependencies.pyo3]
version = "0.22.2"
features = ["auto-initialize"]

3. Copy the sample source:

$ cat src/main.rs 
use pyo3::ffi::c_str;
use pyo3::prelude::*;
use pyo3::types::IntoPyDict;

fn main() -> PyResult<()> {
    Python::with_gil(|py| {
        let sys = py.import("sys")?;
        let version: String = sys.getattr("version")?.extract()?;

        let locals = [("os", py.import("os")?)].into_py_dict(py);
        let code = c_str!("os.getenv('USER') or os.getenv('USERNAME') or 'Unknown'");
        let user: String = py.eval(code, None, Some(&locals))?.extract()?;

        println!("Hello {}, I'm Python {}", user, version);
        Ok(())
    })
}

Backtrace

$ cargo build
   Compiling once_cell v1.19.0
   Compiling cfg-if v1.0.0
   Compiling unindent v0.2.3
   Compiling libc v0.2.158
   Compiling memoffset v0.9.1
   Compiling pyo3-build-config v0.22.2
   Compiling pyo3-macros-backend v0.22.2
   Compiling pyo3-ffi v0.22.2
   Compiling pyo3 v0.22.2
   Compiling pyo3-macros v0.22.2
   Compiling pytest v0.1.0 (/home/haydon/workspace/py03-example/pytest)
warning: unused import: `pyo3::types::IntoPyDict`
 --> src/main.rs:3:5
  |
3 | use pyo3::types::IntoPyDict;
  |     ^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` on by default

error[E0599]: no method named `import` found for struct `pyo3::Python` in the current scope
 --> src/main.rs:7:22
  |
7 |         let sys = py.import("sys")?;
  |                      ^^^^^^
  |
help: there is a method `import_bound` with a similar name
  |
7 |         let sys = py.import_bound("sys")?;
  |                      ~~~~~~~~~~~~

error[E0599]: no method named `import` found for struct `pyo3::Python` in the current scope
  --> src/main.rs:10:33
   |
10 |         let locals = [("os", py.import("os")?)].into_py_dict(py);
   |                                 ^^^^^^
   |
help: there is a method `import_bound` with a similar name
   |
10 |         let locals = [("os", py.import_bound("os")?)].into_py_dict(py);
   |                                 ~~~~~~~~~~~~

error[E0599]: no method named `eval` found for struct `pyo3::Python` in the current scope
  --> src/main.rs:12:31
   |
12 |         let user: String = py.eval(code, None, Some(&locals))?.extract()?;
   |                               ^^^^ method not found in `Python<'_>`

For more information about this error, try `rustc --explain E0599`.
warning: `pytest` (bin "pytest") generated 1 warning
error: could not compile `pytest` (bin "pytest") due to 3 previous errors; 1 warning emitted

Your operating system and version

Kernel: Linux 6.10.9-arch1-1

Your Python version (python --version)

Python 3.12.5

Your Rust version (rustc --version)

rustc 1.81.0 (eeb90cda1 2024-09-04)

Your PyO3 version

0.22.2

How did you install python? Did you use a virtualenv?

system provided (via pacman).
Yes created a venv using python -m venv .

Additional Info

No response

[LilyFoote]

The problem here is that you're using the docs for the as-yet-unreleased 0.23 version, but the 0.22.2 version for your code.

[LilyFoote]

Reopened because the README should be clearer about this.

[Mossman1215]

hello, I have also experienced this issue and fixed the example based on suggestions from rust-analyser

it seems like there's been _bound added to some of the functions that are called in the readme

I have put the version that worked on my demo project into this pull request #4551

I am a novice with rust and like the concept of the library.