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+
+:mod:`uuid` --- UUID objects according to RFC 4122
+==================================================
+
+.. module:: uuid
+ :synopsis: UUID objects (universally unique identifiers) according to RFC 4122
+.. moduleauthor:: Ka-Ping Yee <ping@zesty.ca>
+.. sectionauthor:: George Yoshida <quiver@users.sourceforge.net>
+
+
+.. versionadded:: 2.5
+
+This module provides immutable :class:`UUID` objects (the :class:`UUID` class)
+and the functions :func:`uuid1`, :func:`uuid3`, :func:`uuid4`, :func:`uuid5` for
+generating version 1, 3, 4, and 5 UUIDs as specified in :rfc:`4122`.
+
+If all you want is a unique ID, you should probably call :func:`uuid1` or
+:func:`uuid4`. Note that :func:`uuid1` may compromise privacy since it creates
+a UUID containing the computer's network address. :func:`uuid4` creates a
+random UUID.
+
+
+.. class:: UUID([hex[, bytes[, bytes_le[, fields[, int[, version]]]]]])
+
+ Create a UUID from either a string of 32 hexadecimal digits, a string of 16
+ bytes as the *bytes* argument, a string of 16 bytes in little-endian order as
+ the *bytes_le* argument, a tuple of six integers (32-bit *time_low*, 16-bit
+ *time_mid*, 16-bit *time_hi_version*, 8-bit *clock_seq_hi_variant*, 8-bit
+ *clock_seq_low*, 48-bit *node*) as the *fields* argument, or a single 128-bit
+ integer as the *int* argument. When a string of hex digits is given, curly
+ braces, hyphens, and a URN prefix are all optional. For example, these
+ expressions all yield the same UUID::
+
+ UUID('{12345678-1234-5678-1234-567812345678}')
+ UUID('12345678123456781234567812345678')
+ UUID('urn:uuid:12345678-1234-5678-1234-567812345678')
+ UUID(bytes='\x12\x34\x56\x78'*4)
+ UUID(bytes_le='\x78\x56\x34\x12\x34\x12\x78\x56' +
+ '\x12\x34\x56\x78\x12\x34\x56\x78')
+ UUID(fields=(0x12345678, 0x1234, 0x5678, 0x12, 0x34, 0x567812345678))
+ UUID(int=0x12345678123456781234567812345678)
+
+ Exactly one of *hex*, *bytes*, *bytes_le*, *fields*, or *int* must be given.
+ The *version* argument is optional; if given, the resulting UUID will have its
+ variant and version number set according to RFC 4122, overriding bits in the
+ given *hex*, *bytes*, *bytes_le*, *fields*, or *int*.
+
+:class:`UUID` instances have these read-only attributes:
+
+
+.. attribute:: UUID.bytes
+
+ The UUID as a 16-byte string (containing the six integer fields in big-endian
+ byte order).
+
+
+.. attribute:: UUID.bytes_le
+
+ The UUID as a 16-byte string (with *time_low*, *time_mid*, and *time_hi_version*
+ in little-endian byte order).
+
+
+.. attribute:: UUID.fields
+
+ A tuple of the six integer fields of the UUID, which are also available as six
+ individual attributes and two derived attributes:
+
+ +------------------------------+-------------------------------+
+ | Field | Meaning |
+ +==============================+===============================+
+ | :attr:`time_low` | the first 32 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`time_mid` | the next 16 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`time_hi_version` | the next 16 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`clock_seq_hi_variant` | the next 8 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`clock_seq_low` | the next 8 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`node` | the last 48 bits of the UUID |
+ +------------------------------+-------------------------------+
+ | :attr:`time` | the 60-bit timestamp |
+ +------------------------------+-------------------------------+
+ | :attr:`clock_seq` | the 14-bit sequence number |
+ +------------------------------+-------------------------------+
+
+
+.. attribute:: UUID.hex
+
+ The UUID as a 32-character hexadecimal string.
+
+
+.. attribute:: UUID.int
+
+ The UUID as a 128-bit integer.
+
+
+.. attribute:: UUID.urn
+
+ The UUID as a URN as specified in RFC 4122.
+
+
+.. attribute:: UUID.variant
+
+ The UUID variant, which determines the internal layout of the UUID. This will be
+ one of the integer constants :const:`RESERVED_NCS`, :const:`RFC_4122`,
+ :const:`RESERVED_MICROSOFT`, or :const:`RESERVED_FUTURE`.
+
+
+.. attribute:: UUID.version
+
+ The UUID version number (1 through 5, meaningful only when the variant is
+ :const:`RFC_4122`).
+
+The :mod:`uuid` module defines the following functions:
+
+
+.. function:: getnode()
+
+ Get the hardware address as a 48-bit positive integer. The first time this
+ runs, it may launch a separate program, which could be quite slow. If all
+ attempts to obtain the hardware address fail, we choose a random 48-bit number
+ with its eighth bit set to 1 as recommended in RFC 4122. "Hardware address"
+ means the MAC address of a network interface, and on a machine with multiple
+ network interfaces the MAC address of any one of them may be returned.
+
+.. index:: single: getnode
+
+
+.. function:: uuid1([node[, clock_seq]])
+
+ Generate a UUID from a host ID, sequence number, and the current time. If *node*
+ is not given, :func:`getnode` is used to obtain the hardware address. If
+ *clock_seq* is given, it is used as the sequence number; otherwise a random
+ 14-bit sequence number is chosen.
+
+.. index:: single: uuid1
+
+
+.. function:: uuid3(namespace, name)
+
+ Generate a UUID based on the MD5 hash of a namespace identifier (which is a
+ UUID) and a name (which is a string).
+
+.. index:: single: uuid3
+
+
+.. function:: uuid4()
+
+ Generate a random UUID.
+
+.. index:: single: uuid4
+
+
+.. function:: uuid5(namespace, name)
+
+ Generate a UUID based on the SHA-1 hash of a namespace identifier (which is a
+ UUID) and a name (which is a string).
+
+.. index:: single: uuid5
+
+The :mod:`uuid` module defines the following namespace identifiers for use with
+:func:`uuid3` or :func:`uuid5`.
+
+
+.. data:: NAMESPACE_DNS
+
+ When this namespace is specified, the *name* string is a fully-qualified domain
+ name.
+
+
+.. data:: NAMESPACE_URL
+
+ When this namespace is specified, the *name* string is a URL.
+
+
+.. data:: NAMESPACE_OID
+
+ When this namespace is specified, the *name* string is an ISO OID.
+
+
+.. data:: NAMESPACE_X500
+
+ When this namespace is specified, the *name* string is an X.500 DN in DER or a
+ text output format.
+
+The :mod:`uuid` module defines the following constants for the possible values
+of the :attr:`variant` attribute:
+
+
+.. data:: RESERVED_NCS
+
+ Reserved for NCS compatibility.
+
+
+.. data:: RFC_4122
+
+ Specifies the UUID layout given in :rfc:`4122`.
+
+
+.. data:: RESERVED_MICROSOFT
+
+ Reserved for Microsoft compatibility.
+
+
+.. data:: RESERVED_FUTURE
+
+ Reserved for future definition.
+
+
+.. seealso::
+
+ :rfc:`4122` - A Universally Unique IDentifier (UUID) URN Namespace
+ This specification defines a Uniform Resource Name namespace for UUIDs, the
+ internal format of UUIDs, and methods of generating UUIDs.
+
+
+.. _uuid-example:
+
+Example
+-------
+
+Here are some examples of typical usage of the :mod:`uuid` module::
+
+ >>> import uuid
+
+ # make a UUID based on the host ID and current time
+ >>> uuid.uuid1()
+ UUID('a8098c1a-f86e-11da-bd1a-00112444be1e')
+
+ # make a UUID using an MD5 hash of a namespace UUID and a name
+ >>> uuid.uuid3(uuid.NAMESPACE_DNS, 'python.org')
+ UUID('6fa459ea-ee8a-3ca4-894e-db77e160355e')
+
+ # make a random UUID
+ >>> uuid.uuid4()
+ UUID('16fd2706-8baf-433b-82eb-8c7fada847da')
+
+ # make a UUID using a SHA-1 hash of a namespace UUID and a name
+ >>> uuid.uuid5(uuid.NAMESPACE_DNS, 'python.org')
+ UUID('886313e1-3b8a-5372-9b90-0c9aee199e5d')
+
+ # make a UUID from a string of hex digits (braces and hyphens ignored)
+ >>> x = uuid.UUID('{00010203-0405-0607-0809-0a0b0c0d0e0f}')
+
+ # convert a UUID to a string of hex digits in standard form
+ >>> str(x)
+ '00010203-0405-0607-0809-0a0b0c0d0e0f'
+
+ # get the raw 16 bytes of the UUID
+ >>> x.bytes
+ '\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f'
+
+ # make a UUID from a 16-byte string
+ >>> uuid.UUID(bytes=x.bytes)
+ UUID('00010203-0405-0607-0809-0a0b0c0d0e0f')
+