brownie steps to compile, deploy and interact on ropsten

Question

I have created a smart contract and deployed it on ropsten with brownie framework.

Here are the steps I've done:

1. Run the command:

   $ brownie init projet1
   

2. I have created my contract in contracts/Contrat1.vy file

3. I have run:

   $ brownie compile
   

4. I have created an Ethereum account and I've sent some ether on it:

   $ brownie accounts generate mon_account2
   

5. I have created this file for deployment: scripts/deploiement.py:

     from brownie import Contrat1, accounts
   
     def main():
       compte = accounts.load('mon_account2')
       t = Contrat1.deploy({'from': compte})
   

6. I have created a project on infura and I've got a project id

7. I have created an account and an API TOKEN KEY on etherscan

8. I have run:

   $ export WEB3_INFURA_PROJECT_ID=<my_infura_projectid>
   $ export ETHERSCAN_TOKEN=<my_etherscan_api_token_key>
   

9. I have run:

   $ brownie run deploiement --network ropsten
   

At this step, my contract is deployed on ropsten. Its deployment address is displayed on screen.

10. Now I want to interact with this contract. So I have run:

    $ brownie console --network ropsten
    provider = Contract.from_explorer('<my_contract's_deployment_address>')
    

11. I suppose I can now send transactions through provider variable.

Here are my questions:

• My infura secret was not asked. So I suppose anyone can call my infura project url ?
• Is there a way to avoid to work with Etherscan ? I have worked previously with truffle and it was not necessary to get an Etherscan account for deploying contract.
• Is there a way to avoid to export WEB3_INFURA_PROJECT_ID and ETHERSCAN_TOKEN ? Is there a way to put these values in a project configuration file ?
• When launching Contract.from_explorer, I get this error:

ValueError: Failed to retrieve data from API: Contract source code not verified

How should I fix that?

Thanks a lot