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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 version(self):
 """Return the build date of the gentoo container."""

        try:
            _version = (curl[Gentoo._LATEST_TXT] | \
                    awk['NR==2{print}'] | \
                    cut["-f2", "-d="])().strip()
            _version = datetime.utcfromtimestamp(int(_version))\
                .strftime("%Y-%m-%d")
        except ProcessExecutionError as proc_ex:
            _version = "unknown"
            LOG.error("Could not determine timestamp: %s",
                      str(proc_ex))
        return _version