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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 count(self, paths='', **kwargs):
 """Count the number of commits reachable from this commit :param paths: is an optional path or a list of paths restricting the return value to commits actually containing the paths :param kwargs: Additional options to be passed to git-rev-list. They must not alter the output style of the command, or parsing will yield incorrect results :return: int defining the number of reachable commits"""

        # yes, it makes a difference whether empty paths are given or not in our case
        # as the empty paths version will ignore merge commits for some reason.
        if paths:
            return len(self.repo.git.rev_list(self.hexsha, '--', paths, **kwargs).splitlines())
        else:
            return len(self.repo.git.rev_list(self.hexsha, **kwargs).splitlines())