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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 format_z(cls, offset):
 """ Format `timedelta` into %z """

        sec = offset.total_seconds()
        return '{s}{h:02d}{m:02d}'.format(s='-' if sec<0 else '+', h=abs(int(sec/3600)), m=int((sec%3600)/60))