Change the way a Printer is used by the worker

src/printer.py

@@ -75,6 +75,7 @@ class Printer(ABC):
         self.ready = False
         self.printer_type = printer_type
         self._lock = threading.Lock()
+        self.used = False
 
     @abstractmethod
     def _has_paper(self) -> bool:
@@ -88,6 +89,13 @@ class Printer(ABC):
     def print_task(self, task_type, data) -> None:
         """Takes a PrintTask and executes it"""
 
+    def use_printer(self) -> None:
+        """Marks the printer as being used """
+        self.used = True
+
+    def free_printer(self) -> None:
+        """Marks the printer as being not used, it's available."""
+        self.used = False
 
 class EscPosPrinter(Printer):
     """