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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 p_value_calc(TP, POP, NIR):
 """ Calculate p_value. :param TP: true positive :type TP : dict :param POP: population :type POP : int :param NIR: no information rate :type NIR : float :return: p_value as float """

    try:
        n = POP
        x = sum(list(TP.values()))
        p = NIR
        result = 0
        for j in range(x):
            result += ncr(n, j) * (p ** j) * ((1 - p) ** (n - j))
        return 1 - result
    except Exception:
        return "None"