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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, session_key):
 """ Checks to see if a session currently exists in DynamoDB. :rtype: bool :returns: ``True`` if a session with the given key exists in the DB, ``False`` if not. """


        response = self.table.get_item(
            Key={'session_key': session_key},
            ConsistentRead=ALWAYS_CONSISTENT)
        if 'Item' in response:
            return True
        else:
            return False