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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 ridgecircle(self, x, expo=0.5):
 """happy cat by HG Beyer"""

        a = len(x)
        s = sum(x**2)
        return ((s - a)**2)**(expo / 2) + s / a + sum(x) / a