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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 process_exclusion_criteria(exclusion_criteria):
 """ Parses an exclusion critera string to get the function and threshold. Parameters exclusion_criteria : list list of strings where each string is of the format [relation][threshold]. E.g. \'<0.5\' or \'>=1\' Returns ------- relfun : list list of numpy functions for the exclusion criteria threshold : list list of floats for threshold for each relfun """

    relfun = []
    threshold = []
    for ec in exclusion_criteria:
        if ec[0:2] == '>=':
            relfun.append(np.greater_equal)
            threshold.append(float(ec[2:]))
        elif ec[0:2] == '<=':
            relfun.append(np.less_equal)
            threshold.append(float(ec[2:]))
        elif ec[0] == '>':
            relfun.append(np.greater)
            threshold.append(float(ec[1:]))
        elif ec[0] == '<':
            relfun.append(np.less)
            threshold.append(float(ec[1:]))
        else:
            raise ValueError('exclusion crieria must being with >,<,>= or <=')
    return relfun, threshold