let string := 'this is a secure string'
print('string:', string)
print('md5Hex(string):', md5Hex(string))
print('md5Hex(null):', md5Hex(null))
print('sha256Hex(string):', sha256Hex(string))
print('sha256Hex(null):', sha256Hex(null))

let data := ['1', 'string', 'more', 'keys']
print('data:', data)
print('sha256HmacChainHex(data):', sha256HmacChainHex(data))