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\section{\module{md5} ---         MD5 message digest algorithm} \declaremodule{builtin}{md5}\modulesynopsis{RSA's MD5 message digest algorithm.} \deprecated{2.5}{Use the \refmodule{hashlib} module instead.} This module implements the interface to RSA's MD5 message digest\index{message digest, MD5}algorithm (see also Internet \rfc{1321}).  Its use is quitestraightforward:\ use \function{new()} to create an md5 object.You can now feed this object with arbitrary strings using the\method{update()} method, and at any point you can ask it for the\dfn{digest} (a strong kind of 128-bit checksum,a.k.a. ``fingerprint'') of the concatenation of the strings fed to itso far using the \method{digest()} method.\index{checksum!MD5} For example, to obtain the digest of the string \code{'Nobody inspectsthe spammish repetition'}: \begin{verbatim}>>> 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'\end{verbatim} More condensed: \begin{verbatim}>>> md5.new("Nobody inspects the spammish repetition").digest()'\xbbd\x9c\x83\xdd\x1e\xa5\xc9\xd9\xde\xc9\xa1\x8d\xf0\xff\xe9'\end{verbatim} The following values are provided as constants in the module and asattributes of the md5 objects returned by \function{new()}: \begin{datadesc}{digest_size}  The size of the resulting digest in bytes.  This is always  \code{16}.\end{datadesc} The md5 module provides the following functions: \begin{funcdesc}{new}{\optional{arg}}Return a new md5 object.  If \var{arg} is present, the method call\code{update(\var{arg})} is made.\end{funcdesc} \begin{funcdesc}{md5}{\optional{arg}}For backward compatibility reasons, this is an alternative name for the\function{new()} function.\end{funcdesc} An md5 object has the following methods: \begin{methoddesc}[md5]{update}{arg}Update the md5 object with the string \var{arg}.  Repeated calls areequivalent to a single call with the concatenation of all thearguments: \code{m.update(a); m.update(b)} is equivalent to\code{m.update(a+b)}.\end{methoddesc} \begin{methoddesc}[md5]{digest}{}Return the digest of the strings passed to the \method{update()}method so far.  This is a 16-byte string which may containnon-\ASCII{} characters, including null bytes.\end{methoddesc} \begin{methoddesc}[md5]{hexdigest}{}Like \method{digest()} except the digest is returned as a string oflength 32, containing only hexadecimal digits.  This may be used to exchange the value safely in email or other non-binaryenvironments.\end{methoddesc} \begin{methoddesc}[md5]{copy}{}Return a copy (``clone'') of the md5 object.  This can be used toefficiently compute the digests of strings that share a common initialsubstring.\end{methoddesc}  \begin{seealso}  \seemodule{sha}{Similar module implementing the Secure Hash                  Algorithm (SHA).  The SHA algorithm is considered a                  more secure hash.}\end{seealso}