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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 parse_interpolations(self, string):
 """Parse a string for interpolations, but don't treat anything else as Sass syntax. Returns an AST node. """

        # Shortcut: if there are no #s in the string in the first place, it
        # must not have any interpolations, right?
        if '#' not in string:
            return Literal(String.unquoted(string))
        return self.parse_expression(string, 'goal_interpolated_literal')