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(python2.1-lib.info)md5

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MD5 message digest algorithm
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RSA's MD5 message digest algorithm.

This module implements the interface to RSA's MD5 message digest
algorithm (see also Internet RFC 1321 ).  Its use is quite
straightforward: use `new()' to create an md5 object.  You can now feed
this object with arbitrary strings using the `update()' method, and at
any point you can ask it for the "digest" (a strong kind of 128-bit
checksum, a.k.a. "fingerprint") of the concatenation of the strings fed
to it so far using the `digest()' method.

For example, to obtain the digest of the string `'Nobody inspects the
spammish repetition'':

     >>> import md5
     >>> m = md5.new()
     >>> m.update("Nobody inspects")
     >>> m.update(" the spammish repetition")
     >>> m.digest()
     '\xbbd\x9c\x83\xdd\x1e\xa5\xc9\xd9\xde\xc9\xa1\x8d\xf0\xff\xe9'

More condensed:

     >>> md5.new("Nobody inspects the spammish repetition").digest()
     '\xbbd\x9c\x83\xdd\x1e\xa5\xc9\xd9\xde\xc9\xa1\x8d\xf0\xff\xe9'

`new([arg])'
     Return a new md5 object.  If ARG is present, the method call
     `update(ARG)' is made.

`md5([arg])'
     For backward compatibility reasons, this is an alternative name
     for the `new()' function.

An md5 object has the following methods:

`update(arg)'
     Update the md5 object with the string ARG.  Repeated calls are
     equivalent to a single call with the concatenation of all the
     arguments, i.e. `m.update(a); m.update(b)' is equivalent to
     `m.update(a+b)'.

`digest()'
     Return the digest of the strings passed to the `update()' method
     so far.  This is a 16-byte string which may contain non-ASCII
     characters, including null bytes.

`hexdigest()'
     Like `digest()' except the digest is returned as a string of
     length 32, containing only hexadecimal digits.  This may be used
     to exchange the value safely in email or other non-binary
     environments.

`copy()'
     Return a copy ("clone") of the md5 object.  This can be used to
     efficiently compute the digests of strings that share a common
     initial substring.

See also:
     Note: sha Similar module implementing the Secure Hash Algorithm
     (SHA).  The SHA algorithm is considered a more secure hash.