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error[E0507]: cannot move out of X which is behind a shared reference.

Making a [Nannou App](https://nannou.cc/) that draws a line to the screen. 

My model only contains the window itself and a vector of tuples describing the points and color.
Similar to [this example](https://guide.nannou.cc/tutorials/basics/drawing-2d-shapes.html)(under Drawing Lines) I want to use `polyline()` to draw a vector of (point, color) tuples to the screen. Unlike the example I want the vector to not be generated in the `view()` function but to be part of the model. 
(empty update function is added for completeness' sake)

    use nannou::color::gradient::Gradient;
    use nannou::prelude::*;
    
    fn main() {
        nannou::app(model).update(update).run();
    }

    struct Model {
        // so this is a window id called _window -- I guess.
        _window: window::Id,
        my_line: Vec<(Point2, Hsl)>,
    }

    fn model(app: &App) -> Model {
        let _window = app.new_window().size(512, 512).view(view).build().unwrap();
         // where I define the line that I want to draw to the screen.
        let my_line = vec![
            (pt2(1.3, 2.5), hsl(28.0 / 360.0, 1.0, 0.68)),
            (pt2(-7.0, 2.5), hsl(28.0 / 360.0, 1.0, 0.68)),
        ];
        Model { _window, my_line }
    }

    fn update(_app: &App, _model: &mut Model, _update: Update) {
        // empty for now
    }

The problem is when wanting to draw the line to the screen in the `view()` function.

    fn view(app: &App, _model: &Model, frame: Frame) {
        let draw = app.draw();
        draw.background().color(GRAY);
        draw.polyline().weight(3.0).points_colored(_model.my_line);
        draw.to_frame(app, &frame).unwrap();
    }

The compiler tells me something about wanting to `move` out of `my_line` but that it is not possible because the copy trait is not implemented.

    error[E0507]: cannot move out of `_model.my_line` which is behind a shared reference
      --> src/main.rs:30:48
       |
    30 |     draw.polyline().weight(3.0).points_colored(_model.my_line);
       |                                                ^^^^^^^^^^^^^^ move occurs because `_model.my_line` has type `Vec<(Vec2, nannou::prelude::Hsl)>`, which does not implement the `Copy` trait


I am fairly new to rust and do not understand what is going on.