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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 add_optional_arg_param(self, param_name, layer_index, blob_index):
 """Add an arg param. If there is no such param in .caffemodel fie, silently ignore it."""

        blobs = self.layers[layer_index].blobs
        if blob_index < len(blobs):
            self.add_arg_param(param_name, layer_index, blob_index)