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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 lincc(x, y):
 """ Calculates Lin's concordance correlation coefficient. Usage: alincc(x,y) where x, y are equal-length arrays Returns: Lin's CC """

    covar = cov(x, y) * (len(x) - 1) / float(len(x))  # correct denom to n
    xvar = var(x) * (len(x) - 1) / float(len(x))  # correct denom to n
    yvar = var(y) * (len(y) - 1) / float(len(y))  # correct denom to n
    lincc = (2 * covar) / ((xvar + yvar) + ((mean(x) - mean(y)) ** 2))
    return lincc