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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 _get_rate(self, mag):
 """ Calculate and return the annual occurrence rate for a specific bin. :param mag: Magnitude value corresponding to the center of the bin of interest. :returns: Float number, the annual occurrence rate for the :param mag value. """

        mag_lo = mag - self.bin_width / 2.0
        mag_hi = mag + self.bin_width / 2.0

        if mag >= self.min_mag and mag < self.char_mag - DELTA_CHAR / 2:
            # return rate according to exponential distribution
            return (10 ** (self.a_val - self.b_val * mag_lo)
                    - 10 ** (self.a_val - self.b_val * mag_hi))
        else:
            # return characteristic rate (distributed over the characteristic
            # range) for the given bin width
            return (self.char_rate / DELTA_CHAR) * self.bin_width