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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 molecular_weight(elements):
 """ Return molecular weight of a molecule. Parameters elements : numpy.ndarray An array of all elements (type: str) in a molecule. Returns ------- numpy.float64 A molecular weight of a molecule. """

    return (np.array([atomic_mass[i.upper()] for i in elements]).sum())