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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 utc_strftime(self, format):
 """Format the UTC time using a Python date formatting string. This internally calls the Python ``strftime()`` routine from the Standard Library ``time()`` module, for which you can find a quick reference at ``http://strftime.org/``. If this object is an array of times, then a sequence of strings is returned instead of a single string. """

        tup = self._utc_tuple(_half_second)
        year, month, day, hour, minute, second = tup
        second = second.astype(int)
        zero = zeros_like(year)
        tup = (year, month, day, hour, minute, second, zero, zero, zero)
        if self.shape:
            return [strftime(format, item) for item in zip(*tup)]
        else:
            return strftime(format, tup)