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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 do_keyframes_overlap(self):
 """Checks for keyframs timing overlap. Returns the name of the first keyframs that overlapped."""

        skl = self.sorted_key_list()
        for i in range(len(skl)-1):
            this_time = self.dct[skl[i]]['__abs_time__']
            next_time = self.dct[skl[i+1]]['__abs_time__']
            if abs(next_time-this_time) < 1e-6:
                # key frame times overlap
                return skl[i]
        # Return None if all passed
        return None