[add]: Error handling

app/errors/__init__.py

@@ -0,0 +1 @@
+from .handlers import bad_request, method_not_allowed, not_found

app/errors/handlers.py

@@ -0,0 +1,11 @@
+from flask import jsonify
+from app.helpers.response_helper import ResponseHelper
+
+def method_not_allowed(error):
+    return ResponseHelper.method_not_allowed(message="Method Not Allowed")
+
+def not_found(error):
+    return ResponseHelper.not_found(message="URL Not Found")
+
+def bad_request(error):
+    return ResponseHelper.bad_request(message="Bad Request")