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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 get_by_name(opname, operators):
 """Return operator class instance by name. Parameters opname: str Name of the sklearn class that belongs to a TPOT operator operators: list List of operator classes from operator library Returns ------- ret_op_class: class An operator class """

    ret_op_classes = [op for op in operators if op.__name__ == opname]

    if len(ret_op_classes) == 0:
        raise TypeError('Cannot found operator {} in operator dictionary'.format(opname))
    elif len(ret_op_classes) > 1:
        raise ValueError(
            'Found duplicate operators {} in operator dictionary. Please check '
            'your dictionary file.'.format(opname)
        )
    ret_op_class = ret_op_classes[0]
    return ret_op_class