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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def download_all(self, layers, force=False):
 """ Download a list of layers to the cache Parameters layers list(samcli.commands.local.lib.provider.Layer) List of Layers representing the layer to be downloaded force bool True to download the layer even if it exists already on the system Returns ------- List(Path) List of Paths to where the layer was cached """

        layer_dirs = []
        for layer in layers:
            layer_dirs.append(self.download(layer, force))

        return layer_dirs