init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Utilities/Collections/UnmodifiableSet.cs

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+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections;
+
+public abstract class UnmodifiableSet : ISet, ICollection, IEnumerable
+{
+	public abstract int Count { get; }
+
+	public abstract bool IsEmpty { get; }
+
+	public abstract bool IsFixedSize { get; }
+
+	public virtual bool IsReadOnly => true;
+
+	public abstract bool IsSynchronized { get; }
+
+	public abstract object SyncRoot { get; }
+
+	public virtual void Add(object o)
+	{
+		throw new NotSupportedException();
+	}
+
+	public virtual void AddAll(IEnumerable e)
+	{
+		throw new NotSupportedException();
+	}
+
+	public virtual void Clear()
+	{
+		throw new NotSupportedException();
+	}
+
+	public abstract bool Contains(object o);
+
+	public abstract void CopyTo(Array array, int index);
+
+	public abstract IEnumerator GetEnumerator();
+
+	public virtual void Remove(object o)
+	{
+		throw new NotSupportedException();
+	}
+
+	public virtual void RemoveAll(IEnumerable e)
+	{
+		throw new NotSupportedException();
+	}
+}