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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_canonical(self):
 """Get the canonical output string."""


        # Assemble major, minor, micro version and append `pre`, `post`, or `dev` if needed..
        if self.micro == 0:
            ver = "{}.{}".format(self.major, self.minor)
        else:
            ver = "{}.{}.{}".format(self.major, self.minor, self.micro)
        if self._is_pre():
            ver += '{}{}'.format(REL_MAP[self.release], self.pre)
        if self._is_post():
            ver += ".post{}".format(self.post)
        if self._is_dev():
            ver += ".dev{}".format(self.dev)

        return ver