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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 lately(self, count=15):
 """ Show ``count`` most-recently modified files by mtime Yields: tuple: (strftime-formatted mtime, self.fpath-relative file path) """

        excludes = '|'.join(('*.pyc', '*.swp', '*.bak', '*~'))
        cmd = ('''find . -printf "%%T@ %%p\\n" '''
               '''| egrep -v '%s' '''
               '''| sort -n '''
               '''| tail -n %d''') % (excludes, count)
        op = self.sh(cmd, shell=True)
        for l in op.split('\n'):
            l = l.strip()
            if not l:
                continue
            mtime, fname = l.split(' ', 1)
            mtime = datetime.datetime.fromtimestamp(float(mtime))
            mtimestr = dtformat(mtime)
            yield mtimestr, fname