PBKDF2 hash
Bases: sentry.hashers.BaseHasher
iterations is how many times to hash the password
dkLen is how many bytes to retrieve from the key derived from the password
mac is a module to use to generate message authentication codes. If unset it defaults to the standard hmac module
digest is which hash algorithm to use. If unset it default to the standard sha1 digest.
>>> h = PBKDF2Hasher(1200, 42)
>>> h.hsh("hello", "NaCl")
'NaCl:a2ZywAK8emy0AmTK+8YoVI7er/4EiHMkQLWjnj+O7h0EB0rTnbbx9+ce'