PermissionSet
                    public class PermissionSet : ICollection, IEnumerable, IDeserializationCallback, ISecurityEncodable, IStackWalk
                
                using System.Collections;
using System.Runtime.CompilerServices;
using System.Runtime.Serialization;
using System.Security.Permissions;
namespace System.Security
{
    public class PermissionSet : ICollection, IEnumerable, IDeserializationCallback, ISecurityEncodable, IStackWalk
    {
        public virtual int Count => 0;
        public virtual bool IsReadOnly => false;
        public virtual bool IsSynchronized => false;
        public virtual object SyncRoot => this;
        public PermissionSet(PermissionState state)
        {
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public PermissionSet(PermissionSet permSet)
        {
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public IPermission AddPermission(IPermission perm)
        {
            return AddPermissionImpl(perm);
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        protected virtual IPermission AddPermissionImpl(IPermission perm)
        {
            return null;
        }
        public void Assert()
        {
        }
        public bool ContainsNonCodeAccessPermissions()
        {
            return false;
        }
        [System.Obsolete]
        public static byte[] ConvertPermissionSet(string inFormat, byte[] inData, string outFormat)
        {
            throw new PlatformNotSupportedException(System.SR.PlatformNotSupported_CAS);
        }
        public virtual PermissionSet Copy()
        {
            return new PermissionSet(this);
        }
        public virtual void CopyTo(Array array, int index)
        {
        }
        public void Demand()
        {
        }
        [System.Obsolete]
        public void Deny()
        {
            throw new PlatformNotSupportedException(System.SR.PlatformNotSupported_CAS);
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public override bool Equals(object o)
        {
            return base.Equals(o);
        }
        public virtual void FromXml(SecurityElement et)
        {
        }
        public IEnumerator GetEnumerator()
        {
            return GetEnumeratorImpl();
        }
        protected virtual IEnumerator GetEnumeratorImpl()
        {
            return Array.Empty<object>().GetEnumerator();
        }
        public override int GetHashCode()
        {
            return base.GetHashCode();
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public IPermission GetPermission(Type permClass)
        {
            return GetPermissionImpl(permClass);
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        protected virtual IPermission GetPermissionImpl(Type permClass)
        {
            return null;
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public PermissionSet Intersect(PermissionSet other)
        {
            return null;
        }
        public bool IsEmpty()
        {
            return false;
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public bool IsSubsetOf(PermissionSet target)
        {
            return false;
        }
        public bool IsUnrestricted()
        {
            return false;
        }
        public void PermitOnly()
        {
            throw new PlatformNotSupportedException(System.SR.PlatformNotSupported_CAS);
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public IPermission RemovePermission(Type permClass)
        {
            return RemovePermissionImpl(permClass);
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        protected virtual IPermission RemovePermissionImpl(Type permClass)
        {
            return null;
        }
        public static void RevertAssert()
        {
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public IPermission SetPermission(IPermission perm)
        {
            return SetPermissionImpl(perm);
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        protected virtual IPermission SetPermissionImpl(IPermission perm)
        {
            return null;
        }
        void IDeserializationCallback.OnDeserialization(object sender)
        {
        }
        public override string ToString()
        {
            return base.ToString();
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public virtual SecurityElement ToXml()
        {
            return null;
        }
        [System.Runtime.CompilerServices.NullableContext(2)]
        public PermissionSet Union(PermissionSet other)
        {
            return null;
        }
    }
}