use uuid v4 to generate a unique id randomly.

HashCrc32 returns the CRC32 checksum of the data as a string.

HashMD5 returns the MD5 checksum of the data as a string.

HashSHA1 returns the SHA1 checksum of the data as a string.

HashSHA256 returns the SHA256 checksum of the data as a string.

this ensures that uuid from google is encapsulated in case of future changes.