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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(s):
 """ Parse string representation back into the DenseVector. DenseVector([0.0, 1.0, 2.0, 3.0]) """

        start = s.find('[')
        if start == -1:
            raise ValueError("Array should start with '['.")
        end = s.find(']')
        if end == -1:
            raise ValueError("Array should end with ']'.")
        s = s[start + 1: end]

        try:
            values = [float(val) for val in s.split(',') if val]
        except ValueError:
            raise ValueError("Unable to parse values from %s" % s)
        return DenseVector(values)