First (way too late) commit

Dumping my fever dream coding session into source control finally.

src/df_tools/configuration.py

@@ -0,0 +1,65 @@
+import tomllib
+import tomli_w
+from typing import Optional
+from pathlib import Path
+from pydantic import SecretStr, Field, BaseModel
+from pydantic_settings import BaseSettings, SettingsConfigDict
+
+class ExampleSection(BaseModel):
+    example_key: str = "example_value"
+    maybe_value: Optional[int] = None
+
+class Settings(BaseSettings):
+    default_config_dir: Path = Field(default=Path.home() / ".config", # / "python-boilerplate",
+        description="Default path to user configuration file.", exclude=True)
+    config_file_name: Path = Field(default=Path("python_boilerplate.toml"),
+        description="Name of the configuration file.", exclude=True)
+    logfile: str = "python-boilerplate.log"
+    example_string: str = Field(default="Example Default", description="An example string value.")
+    example_int: Optional[int] = None
+    example_float: Optional[float] = None
+    example_bool: bool = True
+    example_list: list[int] = [1, 2, 3]
+    example_dict: dict[str, str] = {"key": "value", "foo": "bar"}
+    example_section: ExampleSection = ExampleSection()
+
+    model_config = SettingsConfigDict(
+        env_prefix="PYTHON_BOILERPLATE_",
+        env_nested_delimiter="__",
+        env_file_encoding="utf-8",
+        extra="ignore",
+    )
+
+    @classmethod
+    def load(cls, custom_file: Optional[Path | str] = None) -> "Settings":
+        # Use the provided custom file, or look for config file in standard locations
+        if custom_file is not None and Path(custom_file).is_file():
+            config_file = Path(custom_file)
+        elif Path(Path.cwd() / cls().config_file_name).is_file():
+            # Check for config in current directory
+            config_file = Path.cwd() / cls().config_file_name
+        elif Path(cls().default_config_dir / cls().config_file_name).is_file():
+            # Wherever the heck we specified
+            config_file = cls().default_config_dir / cls().config_file_name
+        else:
+            # Return default settings if no config file found
+            return cls()
+
+        if config_file.is_file():
+            with config_file.open("rb") as f:
+                config_data = tomllib.load(f)
+            return cls.model_validate(config_data)
+        
+        return cls()
+    
+    def save(self, custom_file: Optional[Path] = None) -> None:
+        # Use the provided custom file, or look for config file in standard locations
+        if custom_file is not None:
+            config_file = custom_file
+        else:
+            config_file = self.default_config_dir / self.config_file_name
+
+        config_file.parent.mkdir(parents=True, exist_ok=True)
+
+        with config_file.open("wb") as f:
+            tomli_w.dump(self.model_dump(mode="json",exclude_none=True), f)