Study: Switch to logging.

src/Model/Study.py

@@ -2,6 +2,7 @@
 
 import os
 import shutil
+import logging
 from datetime import datetime
 
 from tools import timer, timestamp
@@ -14,6 +15,8 @@ from Model.River import River
 
 from Checker.Study import *
 
+logger = logging.getLogger()
+
 class Study(SQLModel):
     _sub_classes = [
         River,
@@ -81,7 +84,7 @@ class Study(SQLModel):
                 shutil.rmtree(old_dir)
                 os.makedirs(old_dir)
             except Exception as e:
-                print(e)
+                logger.error(e)
 
         fname = fname + "." + str(self._old_save_id)
         filename = os.path.join(fdir, "__old__", fname)
@@ -187,7 +190,7 @@ class Study(SQLModel):
     def _update(self):
         version = self.execute(f"SELECT value FROM info WHERE key='version'")
 
-        print(f"{version[0]} == {self._version}")
+        logger.debug(f"{version[0]} == {self._version}")
         if version[0] == self._version:
             return True
 
@@ -195,7 +198,7 @@ class Study(SQLModel):
             self.execute(f"UPDATE info SET value='{self._version}' WHERE key='version'")
             return True
 
-        print("TODO: update failed")
+        logger.info("TODO: update failed")
         raise NotImplementedMethodeError(self, self._update)
 
     @classmethod