pub fn synthesise_declare_statement_function<T: ReadFromFS, A: ASTImplementation>(
    variable_id: VariableId,
    _overloaded: bool,
    is_async: bool,
    is_generator: bool,
    location: Option<String>,
    internal_marker: Option<InternalFunctionEffect>,
    function: &impl SynthesisableFunction<A>,
    environment: &mut Environment<'_>,
    checking_data: &mut CheckingData<'_, T, A>
)