pub const UUID4: Format;Expand description
Universally Unique Identifier, version 4, value as defined by
https://datatracker.ietf.org/doc/html/rfc4122. The value may be
normalized to entirely lowercase letters. For example, the value
F47AC10B-58CC-0372-8567-0E02B2C3D479 would be normalized to
f47ac10b-58cc-0372-8567-0e02b2c3d479.