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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 construct_asset_path(self, asset_path, css_path, output_filename, variant=None):
 """Return a rewritten asset URL for a stylesheet"""

        public_path = self.absolute_path(asset_path, os.path.dirname(css_path).replace('\\', '/'))
        if self.embeddable(public_path, variant):
            return "__EMBED__%s" % public_path
        if not posixpath.isabs(asset_path):
            asset_path = self.relative_path(public_path, output_filename)
        return asset_path