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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 exists_evaluator(self, index):
 """ Evaluate the given exists match condition for the user attributes. Args: index: Index of the condition to be evaluated. Returns: Boolean: True if the user attributes have a non-null value for the given condition, otherwise False. """

    attr_name = self.condition_data[index][0]
    return self.attributes.get(attr_name) is not None