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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 SQRT(argument):
 """ Computes the square matrix of the argument :param argument: a dataset region field (dataset.field) or metadata (dataset['field']) """

    if isinstance(argument, MetaField):
        return argument._unary_expression("SQRT")
    elif isinstance(argument, RegField):
        return argument._unary_expression("SQRT")
    else:
        raise TypeError("You have to give as input a RegField (dataset.field)"
                        "or a MetaField (dataset['field']")