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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 calc_uncertainty(quantity, sys_unc, mean=True):

 """Calculate the combined standard uncertainty of a quantity."""

    n = len(quantity)
    std = np.nanstd(quantity)
    if mean:
        std /= np.sqrt(n)
    return np.sqrt(std**2 + sys_unc**2)