Python Hashlib: Purpose and Usage Guide

The hashlib module in Python is used for hash algorithms. It offers various hash algorithms such as MD5, SHA1, and SHA256.

The main uses are as follows:

1. Commonly used functions of the hashlib module include:
2. hashlib.md5(): create an MD5 hash object.
3. Create a SHA1 hash object using hashlib.sha1().
4. Create a SHA256 hash object using hashlib.sha256().
5. Common methods of hash objects include:
6. Update the hash value of the hash object by calling this function multiple times.
7. digest(): Returns the binary form of the hash value.
8. hexdigest(): returns the hexadecimal form of the hash value.
9. Specific usage examples:

import hashlib

# 创建MD5哈希对象
md5_obj = hashlib.md5()
# 更新哈希值
md5_obj.update(b"Hello World")
# 获取哈希值的十六进制形式
md5_hex = md5_obj.hexdigest()
print(md5_hex)

# 创建SHA1哈希对象
sha1_obj = hashlib.sha1()
sha1_obj.update(b"Hello World")
sha1_hex = sha1_obj.hexdigest()
print(sha1_hex)

# 创建SHA256哈希对象
sha256_obj = hashlib.sha256()
sha256_obj.update(b"Hello World")
sha256_hex = sha256_obj.hexdigest()
print(sha256_hex)

Output result:

b10a8db164e0754105b7a99be72e3fe5
2ef7bde608ce5404e97d5f042f95f89f1c232871
a591a6d40bf420404a011733cfb7b190d62c65bf0bcda32b57b277d9ad9f146e

The above examples demonstrate how to use the hashlib module for MD5, SHA1, and SHA256 hashing operations. In practical applications, the appropriate hashing algorithm can be chosen based on the specific requirements.