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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 value_count(x, value):
 """ Count occurrences of `value` in time series x. :param x: the time series to calculate the feature of :type x: numpy.ndarray :param value: the value to be counted :type value: int or float :return: the count :rtype: int """

    if not isinstance(x, (np.ndarray, pd.Series)):
        x = np.asarray(x)

    if np.isnan(value):
        return np.isnan(x).sum()
    else:
        return x[x == value].size