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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 mpixel(self, z, n=0):
 """Iteration in Mandlebrot coordinate z."""

        z = z * z + self.c
        if (abs(z) > 2.0):
            return self.color(n)
        n += 1
        if (n > self.max_iter):
            return None
        return self.mpixel(z, n)