Add docstrings to 3 functions in kedro/utils.py (#4022)

* Add docstrings to utility functions

Signed-off-by: Yury Fedotov <yury_fedotov@mckinsey.com>

kedro/utils.py

@@ -31,10 +31,26 @@ def load_obj(obj_path: str, default_obj_path: str = "") -> Any:
 
 
 def _is_databricks() -> bool:
+    """Evaluate if the current run environment is Databricks or not.
+
+    Useful to tailor environment-dependent activities like Kedro magic commands
+    or logging features that Databricks doesn't support.
+
+    Returns:
+        True if run environment is Databricks, otherwise False.
+    """
     return "DATABRICKS_RUNTIME_VERSION" in os.environ
 
 
 def _is_project(project_path: Union[str, Path]) -> bool:
+    """Evaluate if a given path is a root directory of a Kedro project or not.
+
+    Args:
+        project_path: Path to be tested for being a root of a Kedro project.
+
+    Returns:
+        True if a given path is a root directory of a Kedro project, otherwise False.
+    """
     metadata_file = Path(project_path).expanduser().resolve() / _PYPROJECT
     if not metadata_file.is_file():
         return False
@@ -46,6 +62,17 @@ def _is_project(project_path: Union[str, Path]) -> bool:
 
 
 def _find_kedro_project(current_dir: Path) -> Any:  # pragma: no cover
+    """Given a path, find a Kedro project associated with it.
+
+    Can be:
+        - Itself, if a path is a root directory of a Kedro project.
+        - One of its parents, if self is not a Kedro project but one of the parent path is.
+        - None, if neither self nor any parent path is a Kedro project.
+
+    Returns:
+        Kedro project associated with a given path,
+        or None if no relevant Kedro project is found.
+    """
     paths_to_check = [current_dir] + list(current_dir.parents)
     for parent_dir in paths_to_check:
         if _is_project(parent_dir):