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Composing a Transaction with Op_return in Python
Op_return is an effective way to create small amousts of cryptocurrency transactions without having them as a regular transaction. Here’s a step-by-step guide on how to use python to compose a transaction with op_return.
Prerequisites
- You can install theming pip:
PIP Install Hashlib Hmac
. Any transaction larger than 1 kb or containing a value greater than 2^64-1 bytes will be rejected.
Composing a Transaction with Op_return
Data. Here’s an example function that generates a valid op_return transaction:
`python
Hashlib import
From Hmac Import Digest
Def Op_return (Data):
Convert the Input Data to Bytes
Data_Bytes = Data.encode ('UTF-8')
Generate and SHA-256 Hash of the Input Data
hash_hex = Hashlib.Sha256 (Data_Bytes) .hexdigest ()
Create an hmac-sha256 signature using the input data and its hash
Sig = Digest ((Data, Hash_hex), Hashlib.Sha256)
Return {
'Type': 'Op_return',
'Data': Data,
'hash': sig.hex (),
'Index': 0
}
This function
Example Use Case
Here’s an example of how you can use the above function to compose a transl
`python
Data = "My Ethereum Address: 0x1234567890abcdef"
Transaction = Op_return (Data)
Print (Transaction)
Output: {'Type': 'Op_return', ...}
Note that
Handling Errors
. Data, it will be rejected. .
Conclusion
Op_return Python, you can compose transactions that are both efficient and secure. Remember to always validate the input data before using it to construct a transaction. Happy Coding!
