Also inherit init from contextlib.ContextDecorator so it can be u…

…sed as a function decorator

core/functions.py

@@ -24,7 +24,7 @@
 
 #===========================================================================
 
-class init(contextlib.AbstractContextManager):
+class init(contextlib.AbstractContextManager, contextlib.ContextDecorator):
     """Initialize PLAMS environment. Create global ``config`` and the default |JobManager|.
 
     An empty |Settings| instance is created and populated with default settings by executing ``plams_defaults``. The following locations are used to search for the defaults file, in order of precedence:
@@ -37,11 +37,11 @@ class init(contextlib.AbstractContextManager):
 
     Optionally, an additional `dict` (or |Settings| instance) can be provided to the `config_settings` argument which will be used to update the values from the ``plams_defaults``.
 
-    |init| can be either used as a standalone function or in conjunction with the ``with`` statement, the latter option automatically calling |finish| upon exiting the context manager:
+    |init| can be either used as a standalone function, in conjunction with the ``with`` statement or as a decorator, the latter two options automatically calling |finish| upon exiting the context manager:
 
     .. code-block:: python
 
-        >>> from scm.plams import Molecule, Settings, AMSJob, init, finish
+        >>> from scm.plams import Molecule, Settings, AMSJob, AMSResult, init, finish
 
         >>> mol: Molecule = ...
         >>> settings: Settings = ...
@@ -50,6 +50,11 @@ class init(contextlib.AbstractContextManager):
         ...     job1 = AMSJob(molecule=mol, settings=settings)
         ...     result1 = job1.run()
 
+        >>> @init()
+        ... def run_job(mol: Molecule, settings: Settings) -> AMSResult
+        ...     job1 = AMSJob(molecule=mol, settings=settings)
+        ...     return job1.run()
+
         # Equivalently:
         >>> init()
         >>> job2 = AMSJob(molecule=mol, settings=settings)