def METHOD_NAME(self):
    super().METHOD_NAME()
    lines = self._out_file.read().split("\n")
    # Index where SSE records start
    sse_start = None
    for i, line in enumerate(lines):
        if line.startswith("  #  RESIDUE AA STRUCTURE"):
            sse_start = i+1
    if sse_start is None:
        raise ValueError("DSSP file does not contain SSE records")
    # Remove "!" for missing residues
    lines = [
        line for line in lines[sse_start:]
        if len(line) != 0 and line[13] != "!"
    ]
    self._sse = np.zeros(len(lines), dtype="U1")
    # Parse file for SSE letters
    for i, line in enumerate(lines):
        self._sse[i] = line[16]
    self._sse[self._sse == " "] = "C"