Create README.md (#5989)

model_cards/unideeplearning/polibert_sa/README.md

+---
+language: it
+tags:
+- sentiment
+- Italian
+license: MIT
+widget:
+- text: 'Giuseppe Rossi è un ottimo politico'
+---
+
+# 🤗 + polibert_SA - POLItic BERT based Sentiment Analysis
+  
+## Model description  
+  
+This model performs sentiment analysis on Italian political twitter sentences. It was trained starting from an instance of "bert-base-italian-uncased-xxl" and fine-tuned on an Italian dataset of tweets.
+  
+#### Hands-on  
+  
+```python
+import torch
+from torch import nn 
+
+text = "Giueseppe Rossi è un pessimo politico"
+input_ids = tokenizer.encode(text, add_special_tokens=True, return_tensors= 'pt')
+
+logits, = model(input_ids)
+logits = logits.squeeze(0)
+
+prob = nn.functional.softmax(logits, dim=0)
+
+# 0 Negative, 1 Neutral, 2 Positive 
+print(prob.argmax().tolist())
+```  
+  
+#### Hyperparameters
+
+- Optimizer: **AdamW** with learning rate of **2e-5**, epsilon of **1e-8**
+- Max epochs: **2**
+- Batch size: **16**
+
+## Acknowledgments
+
+Thanks to the support from: 
+the [Hugging Face](https://huggingface.co/), Unione Professionisti (https://www.unioneprofessionisti.com/)