Update 4_project_metadata.md

Author: priya-gitTest

episodes/4_project_metadata.md

@@ -20,35 +20,14 @@ exercises: 10
 
 ## Introduction
 
-In the previous lesson, we briefly introduced `pixi.toml`. In this lesson, we shall focus on `pyproject.toml`, which is the most widely used configuration format for Python projects.
+In the previous lesson, we briefly looked into `pyproject.toml`. In this lesson, we shall focus a bit more in detail on `pyproject.toml`, which is the most widely used configuration format for Python projects.
 Please note, for projects managed with Pixi, either `pyproject.toml` or `pixi.toml` may be employed. The primary distinction lies in syntax, so you need only ensure that you follow the appropriate conventions.
 
-To initialise a project using `pyproject.toml`, run the following command:
-```bash
-pixi init --format pyproject
-```
-```output
-✔ Created .../greet_me/pyproject.toml
-```
-## Whats inside `pyproject.toml`
-
-- Manifest metadata
-```toml
-[project]
-name = "greet_me"
-version = "0.1.0"
-description = "greet_me Pixi-managed package"
-authors = [{ name = "Priyanka", email = "" }]
-readme = "README.md"
-license = { text = "MIT" }
-requires-python = ">=3.11"
-dependencies = []
-```
 ## The `[build-system]` table
 
 This section of a `pyproject.toml` file informs packaging tools such as `pip` which software is required to build your project. It specifies the **build backend** responsible for producing distributable packages such as wheels (`.whl`) or source distributions (`.sdist`).
 
-This section was introduced by **PEP 518** and is essential for modern Python packaging.
+This section was introduced by **[PEP 518]**(https://peps.python.org/pep-0518/) and is essential for modern Python packaging.
 It has two main keys:
 
 1. `requires`: A list of packages required to build the project. These are downloaded and installed into a temporary, isolated environment prior to the build process. The build backend itself must also be listed here.
@@ -59,7 +38,11 @@ It has two main keys:
 requires = ["hatchling"]
 build-backend = "hatchling.build"
 ```
-- Editable Installation
+Some other build tools to read are 
+- [pdm.backend](https://backend.pdm-project.org)
+- [mesonpy](https://mesonbuild.com/meson-python/)
+
+## Editable Installation
 
 Projects may be installed in editable mode, which allows you to make changes to the source code and have them reflected immediately in the environment without reinstallation. For example, the `greet_me` package can be added as an editable dependency.
 
@@ -68,83 +51,49 @@ Projects may be installed in editable mode, which allows you to make changes to
 greet_me = { path = ".", editable = true }
 ```
 
-- Dependency Management
+## Dependency Management
   For dependency handling, the pyproject.toml file should include the requires-python field, which specifies the supported Python versions. For example:
 ```toml
 requires-python = ">=3.11, <3.12"
 ```
- In a `pixi.toml` file, the syntax would differ slightly, but the purpose remains the same.
- 
- Additional sections in `pyproject.toml` may include:
+Additional sections in `pyproject.toml` may include:
   `[tool.pixi.workspace]`: Defines project-wide settings, including package sources and target platforms for resolution.  
   `[tool.pixi.pypi-dependencies]` : Declares the dependencies to be installed from PyPI (or equivalent sources). These are the external libraries required by the project.
 
-```toml
-[project]
-name = "greet_me"
-requires-python = ">=3.11"
-
-[tool.pixi.workspace]
-channels = ["conda-forge"]
-platforms = ["linux-64", "win-64"]
-
-[tool.pixi.pypi-dependencies]
-requests = ">=2.31.0,<3"
-```
 You can specify a range or multiple supported Python versions using the syntax below.
 ```toml
 requires-python = ">=3.11, <3.12"
 ```
-If you were using `pixi.toml` file, the equivalent syntax would be 
-```toml
-[tool.pixi.workspace]
-name = "greet_me"
-channels = ["conda-forge"]
-platforms = ["linux-64", "win-64"]
-
-[tool.pixi.pypi-dependencies]
-python = ">=3.11"
-
-[tool.pixi.tasks]
-```
-- Tasks
-
-The `tasks` section allows you to define custom commands or scripts that should be executed before packaging. These tasks may specify inputs, outputs, or dependencies, enabling you to automate steps in your workflow. You can specify `inputs`, `outputs` or `depends-on` tasks.
-
-```toml
-[tool.pixi.tasks]
-# This command will only be defined on Windows
-greet  = { cmd = "echo 'Happy Python Packaging!'" }
-```
 Final `pyproject.toml` should look like this below, for reference.
 
 ```toml
 [project]
 authors = [{name = "Priyanka O"}]
 dependencies = []
-name = "po_greet_me"
+name = "greet_me"
 requires-python = ">= 3.11"
 version = "0.1.2"
 description = "greet_me Pixi-managed package"
+readme = "README.md"
 
 [build-system]
 build-backend = "hatchling.build"
 requires = ["hatchling"]
 
-[tool.hatch.build.targets.wheel]
-packages = ["my_package"]
-
 [tool.pixi.workspace]
 channels = ["conda-forge"]
 platforms = ["linux-64"]
 
 [tool.pixi.pypi-dependencies]
-greet_me = { path = ".", editable = true }
 requests = ">=2.32.5,<3"
+greet_me = { path = ".", editable = true }
 
 [tool.pixi.tasks]
-greet  = { cmd = "echo 'Happy Python Packaging!'" }
+start = "python -c 'from greet_me import happy; print(happy.greet_happy())'"
 ```
+
+For insipiration, also check [here](https://github.com/prefix-dev/parselmouth/blob/main/pyproject.toml)
+
 ## Lockfiles
 A **lockfile** contains the complete set of dependencies, including specific versions, required to reproduce the project environment. It is automatically generated based on the dependencies listed in the `.toml` file, ensuring that builds remain consistent and reproducible.