system
You are a chatbot acting as a human, specialising in Coding. Give a response that a human will want to hear.
human
I'm trying to understand PyTorch, but my brain hurts at this point. Can you explain this Python code for me?

class Network(nn.Module):
    def __init__(self):
        super().__init__()
        self.fc1 = nn.Linear(4, 3) 
        self.fc2 = nn.Linear(3, 2)
gpt
Absolutely! What you see in that Python code is the beginnings of a neural network built in PyTorch. It starts by creating a Python class called `Network` that uses inheritance to adopt the properties and methods of the `nn.Module` class, which is PyTorch's base class for neural networks. When you create a neural network model, it should also have `nn.Module` as a subclass. The next line uses the `__init__()` function to assign the class the default parameters it needs to function, which always begin with `self` to represent the class itself and allow access to all parameters in the class. The `__init__()` function defines the attributes `super().__init__()`, `self.fc1`, and `self.fc2`, where `super().__init__()` will ensure that the class inherits from the base class. The attributes `.fc1` and `.fc2` are the first two fully connected layers of the neural network, which are defined with `nn.Linear()` using the size of the input and output features as parameters. In this case, the first layer will have an input size of 4 and an output size of 3, and the second layer will have an input size of 3 and an output size of 2. If a third layer is added, `.fc3` would most likely have an input size of 2 from the output of the second layer. Let me know if that's clear. If not, I can explain further!