def add(buffer, entropy):
if not isinstance(buffer, bytes):<EOL><INDENT>raise TypeError("<STR_LIT>")<EOL><DEDENT>if not isinstance(entropy, int):<EOL><INDENT>raise TypeError("<STR_LIT>")<EOL><DEDENT>_lib.RAND_add(buffer, len(buffer), entropy)<EOL>
Mix bytes from *string* into the PRNG state.

The *entropy* argument is (the lower bound of) an estimate of how much
randomness is contained in *string*, measured in bytes.

For more information, see e.g. :rfc:`1750`.

This function is only relevant if you are forking Python processes and
need to reseed the CSPRNG after fork.

:param buffer: Buffer with random data.
:param entropy: The entropy (in bytes) measurement of the buffer.

:return: :obj:`None`