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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 access_token(self, value, request):
 """ Try to get the `AccessToken` associated with the provided token. *The provided value must pass `BearerHandler.validate()`* """


        if self.validate(value, request) is not None:
            return None
        
        access_token = AccessToken.objects.for_token(value)
        
        return access_token