Update README.md

Added example usage. It SHOULD work

README.md

@@ -13,6 +13,23 @@ metrics:
 
 This is a finetuning of a MarianMT pretrained on Chinese-English. The target language pair is Vietnamese-English.
 
+### Example
+```
+%%capture
+!pip install transformers transformers[sentencepiece]
+
+from transformers import AutoModelForSeq2SeqLM, AutoTokenizer
+# Download the pretrained model for English-Vietnamese available on the hub
+model = AutoModelForSeq2SeqLM.from_pretrained("CLAck/vi-en")
+
+tokenizer = AutoTokenizer.from_pretrained("CLAck/vi-en")
+
+sentence = your_vietnamese_sentence
+# This token is needed to identify the source language
+input_sentence = "<2vi> " + sentence 
+translated = model.generate(**tokenizer(input_sentence, return_tensors="pt", padding=True))
+output_sentence = [tokenizer.decode(t, skip_special_tokens=True) for t in translated]
+```
 
 ### Training results