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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 append(self, content, binary=False, encoding=None):
 """Appends the given content to the file. Existing content is preserved. Returns true if successful, false otherwise."""

        mode = "ab" if binary else "a"
        return self._write(content, mode, encoding=encoding, linesep=False)