You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: export_alias.rs
    path of file: ./repos/nushell/crates/nu-cmd-lang/src/core_commands
    
    the code of the file until where you have to start completion: use nu_protocol::ast::Call;
use nu_protocol::engine:
    
    fn signature(&self) -> nu_protocol::Signature {
        Signature::build("export alias")
            .input_output_types(vec![(Type::Nothing, Type::Nothing)])
            .required("name", SyntaxShape::String, "Name of the alias.")
            .required(
                "initial_value",
                SyntaxShape::Keyword(b"=".to_vec(), Box::new(SyntaxShape::Expression)),
                "Equals sign followed by value.",
            )
            .category(Category::Core)
    }