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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 set_bias(self, bias):
 """ Adjusts the image bias. Bias determines where the color changes start. At low bias, low intensities (i.e., low pixel values) will have non-zero color differences, while at high bias only high pixel values will have non-zero differences Args: bias: float A number between 0 and 1. Note that upon initialization the colormap has a default bias of 0.5. Returns: void """

        self.x_offset += (bias - self._bias)
        self._bias = bias

        self._build_cdict()