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Cryptographically secure random implementation, with fallback on normal random.
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Exception raised when no secure random algorithm is found.
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Internal exception used when a specific random source is not available.
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Factory providing L{secureRandom} and L{insecureRandom} methods.
You shouldn't have to instantiate this class, use the module level
functions instead: it is an implementation detail and could be removed or
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Wrapper around C{os.urandom} that cleanly manage its absence.
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Return a number of secure random bytes.
@param nbytes: number of bytes to generate.
@type nbytes: C{int}
@param fallback: Whether the function should fallback on non-secure
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@type fallback: C{bool}
@return: a string of random bytes.
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Wrapper around C{os.getrandbits}.
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Wrapper around the C{random} module.
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Return a number of non secure random bytes.
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