Ethereum networks (mainnet, testnet) in Blockchain / Solidity - Mini Project: Build & Apply

Understanding Ethereum Networks: Mainnet and Testnet

📖 Scenario: You are learning about Ethereum blockchain networks. Ethereum has a main network called Mainnet where real transactions happen with real money. It also has Testnets where developers test their smart contracts and applications without using real money.In this project, you will create a simple program to store and display information about Ethereum networks.

🎯 Goal: You will build a small program that stores Ethereum network names and their descriptions. Then, you will select a network type and display its details.

📋 What You'll Learn

Create a dictionary with Ethereum network names and their descriptions

Create a variable to select a network name

Use a loop or conditional to find and store the selected network's description

Print the selected network's name and description

💡 Why This Matters

🌍 Real World

Developers use Ethereum testnets to safely test smart contracts and decentralized apps before deploying them on the mainnet where real money is involved.

💼 Career

Understanding Ethereum networks is essential for blockchain developers, testers, and anyone working with decentralized applications to avoid costly mistakes.

1

Create the Ethereum networks dictionary

Create a dictionary called eth_networks with these exact entries: 'mainnet': 'The main Ethereum network with real transactions.', 'goerli': 'A popular Ethereum testnet for testing smart contracts.', 'sepolia': 'Another Ethereum testnet used for development and testing.'

Blockchain / Solidity

# Create the eth_networks dictionary with mainnet, goerli, and sepolia
# Your code here

Need a hint?

Use curly braces {} to create a dictionary. Each entry has a key and a value separated by a colon.

2

Select the Ethereum network to display

Create a variable called selected_network and set it to the string 'goerli' to choose the Goerli testnet.

Blockchain / Solidity

eth_networks = {
    'mainnet': 'The main Ethereum network with real transactions.',
    'goerli': 'A popular Ethereum testnet for testing smart contracts.',
    'sepolia': 'Another Ethereum testnet used for development and testing.'
}
# Set selected_network to 'goerli'
# Your code here

Need a hint?

Assign the string 'goerli' to the variable selected_network.

3

Get the description of the selected network

Create a variable called network_description and set it to the description of the network stored in selected_network from the eth_networks dictionary.

Blockchain / Solidity

eth_networks = {
    'mainnet': 'The main Ethereum network with real transactions.',
    'goerli': 'A popular Ethereum testnet for testing smart contracts.',
    'sepolia': 'Another Ethereum testnet used for development and testing.'
}
selected_network = 'goerli'
# Get the description of the selected network from eth_networks
# Your code here

Need a hint?

Use the selected_network variable as a key to get the value from eth_networks.

4

Display the selected network and its description

Write a print statement to display the selected network name and its description in this exact format: "Network: goerli - A popular Ethereum testnet for testing smart contracts."

Blockchain / Solidity

eth_networks = {
    'mainnet': 'The main Ethereum network with real transactions.',
    'goerli': 'A popular Ethereum testnet for testing smart contracts.',
    'sepolia': 'Another Ethereum testnet used for development and testing.'
}
selected_network = 'goerli'
network_description = eth_networks[selected_network]
# Print the network name and description in the required format
# Your code here

Need a hint?

Use an f-string to combine the selected_network and network_description in the print statement.