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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 to_array(self, variables):
 """ Converts the clamping to a 1-D array with respect to the given variables Parameters variables : list[str] List of variables names Returns ------- `numpy.ndarray`_ 1-D array where position `i` correspond to the sign of the clamped variable at position `i` in the given list of variables .. _numpy.ndarray: http://docs.scipy.org/doc/numpy/reference/generated/numpy.ndarray.html#numpy.ndarray """

        arr = np.zeros(len(variables), np.int8)
        dc = dict(self)

        for i, var in enumerate(variables):
            arr[i] = dc.get(var, arr[i])

        return arr