<PackageReference Include="System.Security.Permissions" Version="5.0.0-rc.1.20451.14" />

FileCodeGroup

public sealed class FileCodeGroup : CodeGroup
Grants permission to manipulate files located in the code assemblies to code assemblies that match the membership condition. This class cannot be inherited.
using System.Security.Permissions; namespace System.Security.Policy { public sealed class FileCodeGroup : CodeGroup { public override string AttributeString => null; public override string MergeLogic => null; public override string PermissionSetName => null; public FileCodeGroup(IMembershipCondition membershipCondition, FileIOPermissionAccess access) : base(null, null) { } public override CodeGroup Copy() { return null; } protected override void CreateXml(SecurityElement element, PolicyLevel level) { } public override bool Equals(object o) { return base.Equals(o); } public override int GetHashCode() { return base.GetHashCode(); } protected override void ParseXml(SecurityElement e, PolicyLevel level) { } public override PolicyStatement Resolve(Evidence evidence) { return null; } public override CodeGroup ResolveMatchingCodeGroups(Evidence evidence) { return null; } } }