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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 F_calc(TP, FP, FN, beta):
 """ Calculate F-score. :param TP: true positive :type TP : int :param FP: false positive :type FP : int :param FN: false negative :type FN : int :param beta : beta coefficient :type beta : float :return: F score as float """

    try:
        result = ((1 + (beta)**2) * TP) / \
            ((1 + (beta)**2) * TP + FP + (beta**2) * FN)
        return result
    except ZeroDivisionError:
        return "None"