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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 encode(self, inputs, states=None, valid_length=None):
 """Encode the input sequence. Parameters inputs : NDArray states : list of NDArrays or None, default None valid_length : NDArray or None, default None Returns ------- outputs : list Outputs of the encoder. """

        return self.encoder(self.src_embed(inputs), states, valid_length)