Add "How to Use in Transformers" section (#1)

- Add "How to Use in Transformers" section (7556b3864445989b37a9fa09518ec1ae9d9ab105)
- Add PyTorchModelHubMixin (68fd8f2ce00e6898d27a903b5b02cb6419a65bec)

README.md

@@ -75,6 +75,95 @@ Success is defined as having an acceptable catch rate (recall scores for each at
 The inference code is available on [NeMo Curator's GitHub repository](https://github.com/NVIDIA/NeMo-Curator). <br>
 Check out [this example notebook](https://github.com/NVIDIA/NeMo-Curator/tree/main/tutorials/distributed_data_classification) to get started.
 
+## How to Use in Transformers:
+To use this AEGIS classifiers, you must get access to Llama Guard on Hugging Face here: https://huggingface.co/meta-llama/LlamaGuard-7b. Afterwards, you should set up a [user access token](https://huggingface.co/docs/hub/en/security-tokens) and pass that token into the constructor of this classifier.
+
+```python
+import torch
+import torch.nn.functional as F
+from huggingface_hub import PyTorchModelHubMixin
+from peft import PeftModel
+from torch.nn import Dropout, Linear
+from transformers import AutoModelForCausalLM, AutoTokenizer
+
+# Initialize model embedded with AEGIS
+pretrained_model_name_or_path = "meta-llama/LlamaGuard-7b"
+dtype = torch.bfloat16
+token = "hf_1234"  # Replace with your user access token
+device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
+base_model = AutoModelForCausalLM.from_pretrained(pretrained_model_name_or_path, torch_dtype=dtype, token=token).to(device)
+peft_model_name_or_path = "nvidia/Aegis-AI-Content-Safety-LlamaGuard-Defensive-1.0"
+model = PeftModel.from_pretrained(base_model, peft_model_name_or_path)
+
+# Initialize tokenizer
+tokenizer = AutoTokenizer.from_pretrained(
+    pretrained_model_name_or_path=pretrained_model_name_or_path,
+    padding_side="left"
+)
+tokenizer.pad_token = tokenizer.unk_token
+
+class InstructionDataGuardNet(torch.nn.Module, PyTorchModelHubMixin):
+    def __init__(self, input_dim=4096, dropout=0.7):
+        super().__init__()
+        self.input_dim = input_dim
+        self.dropout = Dropout(dropout)
+        self.sigmoid = torch.nn.Sigmoid()
+        self.input_layer = Linear(input_dim, input_dim)
+
+        self.hidden_layer_0 = Linear(input_dim, 2000)
+        self.hidden_layer_1 = Linear(2000, 500)
+        self.hidden_layer_2 = Linear(500, 1)
+
+    def forward(self, x):
+        x = torch.nn.functional.normalize(x, dim=-1)
+        x = self.dropout(x)
+        x = F.relu(self.input_layer(x))
+        x = self.dropout(x)
+        x = F.relu(self.hidden_layer_0(x))
+        x = self.dropout(x)
+        x = F.relu(self.hidden_layer_1(x))
+        x = self.dropout(x)
+        x = self.hidden_layer_2(x)
+        x = self.sigmoid(x)
+        return x
+
+# Load Instruction-Data-Guard classifier
+instruction_data_guard = InstructionDataGuardNet.from_pretrained("nvidia/instruction-data-guard")
+instruction_data_guard = instruction_data_guard.to(device)
+instruction_data_guard = instruction_data_guard.eval()
+
+# Function to compute results
+def get_instruction_data_guard_results(
+    prompts,
+    tokenizer,
+    model,
+    instruction_data_guard,
+    device="cuda",
+):
+    input_ids = tokenizer(prompts, padding=True, return_tensors="pt").to(device)
+    outputs = model.generate(
+        **input_ids,
+        output_hidden_states=True,
+        return_dict_in_generate=True,
+        max_new_tokens=1,
+        pad_token_id=0,
+    )
+    input_tensor = outputs.hidden_states[0][32][:, -1,:].to(torch.float)
+    return instruction_data_guard(input_tensor).flatten().detach().cpu().numpy()
+
+# Prepare sample input
+instruction = "Find a route between San Diego and Phoenix which passes through Nevada"
+input_ = ""
+response = "Drive to Las Vegas with highway 15 and from there drive to Phoenix with highway 93"
+benign_sample =  f"Instruction: {instruction}. Input: {input_}. Response: {response}."
+text_samples = [benign_sample]
+poisoning_scores = get_instruction_data_guard_results(
+    text_samples, tokenizer, model, instruction_data_guard
+)
+print(poisoning_scores)
+# [0.01149639]
+```
+
 ## Ethical Considerations:
 NVIDIA believes Trustworthy AI is a shared responsibility and we have established policies and practices to enable development for a wide array of AI applications.  When downloaded or used in accordance with our terms of service, developers should work with their internal model team to ensure this model meets requirements for the relevant industry and use case and addresses unforeseen product misuse.