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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_default_repo(self):
 """ Go through all the repositories defined in the config file and search for a truthy value for the ``default`` key. If there isn't any return None. """

        for repo in self.get_repos():
            if self.get_safe(repo, 'default') and self.getboolean(repo, 'default'):
                return repo
        return False