feat: StubsIgnoreAttribute for ignoring members or classes by the stu…

…bs generator

Algorithm/UniverseDefinitions.cs

@@ -17,7 +17,6 @@
 using System;
 using System.Linq;
 using Python.Runtime;
-using QuantConnect.Data;
 using System.Collections.Generic;
 using QuantConnect.Data.Fundamental;
 using QuantConnect.Data.UniverseSelection;
@@ -39,6 +38,7 @@ public class UniverseDefinitions
         /// <summary>
         /// Specifies that universe selection should not make changes on this iteration
         /// </summary>
+        [StubsIgnore]
         public Universe.UnchangedUniverse Unchanged => Universe.Unchanged;
 
         /// <summary>

Common/Data/UniverseSelection/Universe.cs

@@ -38,6 +38,7 @@ public abstract class Universe : IDisposable
         /// <summary>
         /// Gets a value indicating that no change to the universe should be made
         /// </summary>
+        [StubsIgnore]
         public static readonly UnchangedUniverse Unchanged = UnchangedUniverse.Instance;
 
         /// <summary>

Common/StubsIgnoreAttribute.cs

@@ -0,0 +1,27 @@
+/*
+ * QUANTCONNECT.COM - Democratizing Finance, Empowering Individuals.
+ * Lean Algorithmic Trading Engine v2.0. Copyright 2014 QuantConnect Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+*/
+
+using System;
+
+namespace QuantConnect
+{
+    /// <summary>P
+    /// Custom attribute used for marking classes, methods, properties, etc. that should be ignored by the stubs generator
+    /// </summary>
+    [AttributeUsage(AttributeTargets.All)]
+    public sealed class StubsIgnoreAttribute : Attribute
+    {
+    }
+}