akubera

    let mutex_a = Arc::new(Mutex::new(0_u32));
    let mutex_b = mutex_a.clone();
    
    let a = mutex_a.lock().unwrap();
    let b = mutex_b.lock().unwrap();
    println!("{}", *a + *b);

  1e10 + 1e-10 = 10000000000.0000000001
  1e10000000000000000000 + 1e-10000000000000000000 = ...

    #[derive(Serialize, Deserialize)]
    pub struct MyStruct {
      #[serde(with = "bigdecimal::serde::json_num")]
      value: BigDecimal,
    }

   >>> def square_vals(x : list):
   ...    return (v * v for v in x)
   ... 
   >>> square_vals([1,2,3])
   <generator object square_vals.<locals>.<genexpr> at 0x786b8511f5e0>

   >>> def square_vals_yields(x: list):
   ...     for v in x:
   ...         yield v * v
   ... 
   >>> square_vals_yields([1,2,3])
   <generator object square_vals_yields at 0x786b851f5ff0>

    >>> sum((v*v for v in x))

    # pyproject.toml
    [build-system]
    requires = ["setuptools"]
    build-backend = "setup"  # import setup.py as the build-module
    backend-path = ["."]

    def build_sdist(sdist_directory, config_settings):
        ...

    def build_wheel(wheel_directory, config_settings, metadata_directory):
        ...

    $ python -m build --config-setting=foo=bar --config-setting=can-spam

    # will call 
    >>> build_sdist("the/dist/dir", {"foo": "bar", "can": "spam"})

    from setuptools.build_meta import build_sdist as setuptools_build_sdist

    def build_sdist(sdist_directory, config_settings):
        # ... code-gen and copy files to source  ...

        # this will call setup.py::setup, to make things extra confusing
        return setuptools_build_sdist(sdist_directory, config_settings)