rate a new DSA key pair.

The algorithm follows Appendix A.1/A.2 and B.1 of `FIPS 186-4`_,
respectively for domain generation and key pair generation.

Args:
  bits (integer):
    Key length, or size (in bits) of the DSA modulus *p*.
    It must be 1024, 2048 or 3072.

  randfunc (callable):
    Random number generation function; it accepts a single integer N
    and return a string of random data N bytes long.
    If not specified, :func:`Cryptodome.Random.get_random_bytes` is used.

  domain (tuple):
    The DSA domain parameters *p*, *q* and *g* as a list of 3
    integers. Size of *p* and *q* must comply to `FIPS 186-4`_.
    If not specified, the parameters are created anew.

Returns:
  :class:`DsaKey` : a new DSA key object

Raises:
  ValueError : when **bits** is too little, too big, or not a multiple of 64.

.. _FIPS 186-4: http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf
r8