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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 construct_sls_str(self, node):
        '''
        Build the SLSString.
        '''

        # Ensure obj is str, not py2 unicode or py3 bytes
        obj = self.construct_scalar(node)
        if six.PY2:
            obj = obj.encode('utf-8')
        return SLSString(obj)