'=> version string /None'

def getVersion(self, agent, word):

    version_markers = (self.version_markers if isinstance(self.version_markers[0], (list, tuple)) else [self.version_markers])
    version_part = agent.split(word, 1)[(-1)]
    for (start, end) in version_markers:
        if (version_part.startswith(start) and (end in version_part)):
            version = version_part[1:]
            if end:
                version = version.split(end)[0]
            if (not self.allow_space_in_version):
                version = version.split()[0]
            return version
