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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 frame(self, frame):
 """ Return a path go the given frame in the sequence. Integer or string digits are treated as a frame number and padding is applied, all other values are passed though. Examples: /foo/bar.0001.exr /foo/bar.#.exr Args: frame (int or str):
 the desired frame number or a char to pass through (ie. #) Returns: str: """

        try:
            zframe = str(int(frame)).zfill(self._zfill)
        except ValueError:
            zframe = frame

        # There may have been no placeholder for frame IDs in
        # the sequence, in which case we don't want to insert
        # a frame ID

        if self._zfill == 0:
            zframe = ""

        return "".join((self._dir, self._base, zframe, self._ext))