'Create a new node derived from a token, with a new token type and
(optionally) new text.
This is invoked from an imaginary node ref on right side of a
rewrite rule as IMAG[$tokenLabel] or IMAG[$tokenLabel "IMAG"].
This should invoke createToken(Token).'

def createFromToken(self, tokenType, fromToken, text=None):

    raise NotImplementedError
