implement backup, fix ret date bug

src/logic/backup.py

@@ -0,0 +1,25 @@
+import os
+import sys
+import shutil
+from src import config
+
+
+class Backup:
+    def __init__(self):
+        self.source_path = config.database.path + "/" + config.database.name
+        self.backup_path = config.database.backupLocation + "/" + config.database.name
+        self.backup = False
+        self.checkpaths()
+
+    def checkpaths(self):
+        if os.path.exists(config.database.backupLocation):
+            self.backup = True
+
+    def createBackup(self):
+        if self.backup:
+            if os.path.exists(self.source_path):
+                if os.path.exists(self.backup_path):
+                    os.remove(self.backup_path)
+                shutil.copy(self.source_path, self.backup_path)
+                return True
+        return False