ENH: Add in new snippet for script structure

Author: HaoZeke

python-script-structure/README.md

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+# How Can You Structure Your Python Script? 
+
+This folder provides the code examples for the Real Python tutorial [How Can You Structure Your Python Script?](https://realpython.com/python-script-structure/).

python-script-structure/iris_summary.py

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+#!/usr/bin/env python3
+
+# /// script
+# requires-python = ">=3.11"
+# dependencies = [
+#   "click==8.1.8",
+#   "pandas==2.2.3",
+#   "rich==14.0.0",
+#   "ucimlrepo==0.0.7",
+# ]
+# ///
+
+import logging
+import sys
+from dataclasses import dataclass, field
+from enum import IntEnum, StrEnum, auto
+from pprint import pformat
+
+import click
+import pandas as pd
+from rich.console import Console, RenderableType, Text
+from rich.logging import RichHandler
+from rich.table import Table
+from ucimlrepo import fetch_ucirepo
+
+logging.basicConfig(
+    level=logging.INFO,
+    format="%(levelname)s - %(message)s",
+    handlers=[RichHandler(rich_tracebacks=True)]
+)
+
+class UCIDataset(IntEnum):
+    IRIS = 53
+
+class IrisVariable(StrEnum):
+    PETAL_LENGTH = "petal length"
+    PETAL_WIDTH = "petal width"
+    SEPAL_WIDTH = "sepal width"
+    SEPAL_LENGTH = "sepal length"
+
+class Operation(StrEnum):
+    SUMMARY = auto()
+    METADATA = auto()
+
+@dataclass
+class DescriptiveStatistics:
+    data: pd.Series
+    mean: float = field(init=False)
+    median: float = field(init=False)
+    mm_diff: float = field(init=False)
+
+    def __post_init__(self):
+        if not isinstance(self.data, pd.Series):
+            raise TypeError(
+                f"data must be a pandas Series, not {type(self.data)}"
+            )
+        self.mean = self.data.mean()
+        self.median = self.data.median()
+        self.mm_diff = self.mean - self.median
+
+    def __str__(self):
+        return pformat(self)
+
+@click.command()
+@click.option(
+    "--operation",
+    default=Operation.SUMMARY,
+    type=click.Choice(Operation),
+    help="Operation to perform: variable summary or dataset metadata",
+)
+@click.option(
+    "--variable",
+    type=click.Choice(IrisVariable),
+    help="Variable to summarize.",
+    required=False,
+)
+def main(operation, variable):
+    """Fetch the Iris dataset from UCI."""
+    console = Console()
+    iris = fetch_iris()
+    if operation is Operation.SUMMARY:
+        if variable:
+            table = generate_table(iris, variable)
+            logging.info(format_rich_for_log(table))
+            logging.info(f"{IrisVariable(variable)} summary:")
+            logging.info(
+                DescriptiveStatistics(
+                    iris.data.features[IrisVariable(variable).value]
+                )
+            )
+        else:
+            logging.info("All variables:")
+            logging.info(pformat(iris.variables))
+    elif operation is Operation.METADATA:
+        logging.info("Metadata summary:")
+        logging.info(pformat(iris.metadata))
+
+def fetch_iris():
+    """Return the Iris dataset from the UCI ML Repository."""
+    logging.info("Fetching Iris dataset...")
+    try:
+        iris_data = fetch_ucirepo(id=UCIDataset.IRIS.value)
+        assert "data" in iris_data.keys(), \
+            "Object does not have expected structure"
+    except Exception as e:
+        logging.critical(f"Failed to correctly fetch Iris dataset: {e}")
+        sys.exit(1)
+    else:
+        logging.info("Iris dataset fetched successfully")
+        return iris_data
+
+def generate_table(dataset, variable):
+    """Generate a formatted table of descriptive statistics for a variable."""
+    column = IrisVariable(variable).value
+    stats = DescriptiveStatistics(dataset.data.features[column])
+    table = Table(title=f"{column} summary")
+    table.add_column("Metric", style="cyan", justify="right")
+    table.add_column("Value", style="magenta")
+    table.add_row("Mean", f"{stats.mean:.2f}")
+    table.add_row("Median", f"{stats.median:.2f}")
+    table.add_row("Mean-Median Diff", f"{stats.mm_diff:.2f}")
+    return table
+
+def format_rich_for_log(renderable, width=100):
+    """Render a rich object to a plain text string suitable for logging."""
+    console = Console(width=width)
+    with console.capture() as capture:
+        console.print(renderable)
+    return Text.from_ansi(capture.get())
+
+if __name__ == "__main__":
+    main()