def blind(m, hashfunc=hashG1):
<EOL>rInv = None<EOL>while not rInv:<EOL><INDENT>r = randomZ()<EOL>rInv = inverse(r, orderGt())<EOL><DEDENT>return rInv, hashfunc(m) * r<EOL>
Blinds an arbitrary string or byte array @m using an ephemeral key @r
that can be used to deblind. Computes: x = H(x)^r
@returns (1/r,x)