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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(self):
 """ Call the exists command to check if the redis key exists for the current field """

        try:
            key = self.key
        except DoesNotExist:
            """
            If the object doesn't exists anymore, its PK is deleted, so the
            "self.key" call will raise a DoesNotExist exception. We catch it
            to return False, as the field doesn't exists too.
            """
            return False
        else:
            return self.connection.exists(key)