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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 csv_dict(d):
 """Format dict to a string with comma-separated values. """

    if len(d) == 0:
        return "{}"
    return "{" + ', '.join(["'{}': {}".format(k, quotable(v))
                            for k, v in d.items()]) + "}"