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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 _find_file(f):
 """Find a config file if possible."""

        if os.path.isabs(f):
            return f
        else:
            for d in Config._dirs:
                _f = os.path.join(d, f)
                if os.path.isfile(_f):
                    return _f
            raise FiggypyError(
                "could not find configuration file {} in dirs {}"
                .format(f, Config._dirs)
            )