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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 walk(self):
 """Walk proposal kernel"""


        if self.verbose > 1:
            print_('\t' + self._id + ' Running Walk proposal kernel')

        # Mask for values to move
        phi = self.phi

        theta = self.walk_theta

        u = random(len(phi))
        z = (theta / (1 + theta)) * (theta * u ** 2 + 2 * u - 1)

        if self._prime:
            xp, x = self.values
        else:
            x, xp = self.values

        if self.verbose > 1:
            print_('\t' + 'Current value = ' + str(x))

        x = x + phi * (x - xp) * z

        if self.verbose > 1:
            print_('\t' + 'Proposed value = ' + str(x))

        self.stochastic.value = x

        # Set proposal adjustment factor
        self.hastings_factor = 0.0