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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 kappa_se_calc(PA, PE, POP):
 """ Calculate kappa standard error. :param PA: observed agreement among raters (overall accuracy) :type PA : float :param PE: hypothetical probability of chance agreement (random accuracy) :type PE : float :param POP: population :type POP:int :return: kappa standard error as float """

    try:
        result = math.sqrt((PA * (1 - PA)) / (POP * ((1 - PE)**2)))
        return result
    except Exception:
        return "None"