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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 _assert_dirs_exist(self, setting_name):
 """Check that the dirs leading up to the given file path exist. Does not check if the file exists. """

        v = self._get_setting(setting_name)
        if (not os.path.isdir(os.path.split(v)[0])) or os.path.isdir(v):
            self.raise_config_error(
                setting_name,
                v,
                str,
                'a file path in an existing directory',
                is_none_allowed=False,
            )