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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 equals(self, other):
 """ Equality of two SSAFiles. Compares :attr:`SSAFile.info`, :attr:`SSAFile.styles` and :attr:`SSAFile.events`. Order of entries in OrderedDicts does not matter. "ScriptType" key in info is considered an implementation detail and thus ignored. Useful mostly in unit tests. Differences are logged at DEBUG level. """


        if isinstance(other, SSAFile):
            for key in set(chain(self.info.keys(), other.info.keys())) - {"ScriptType"}:
                sv, ov = self.info.get(key), other.info.get(key)
                if sv is None:
                    logging.debug("%r missing in self.info", key)
                    return False
                elif ov is None:
                    logging.debug("%r missing in other.info", key)
                    return False
                elif sv != ov:
                    logging.debug("info %r differs (self=%r, other=%r)", key, sv, ov)
                    return False

            for key in set(chain(self.styles.keys(), other.styles.keys())):
                sv, ov = self.styles.get(key), other.styles.get(key)
                if sv is None:
                    logging.debug("%r missing in self.styles", key)
                    return False
                elif ov is None:
                    logging.debug("%r missing in other.styles", key)
                    return False
                elif sv != ov:
                    for k in sv.FIELDS:
                        if getattr(sv, k) != getattr(ov, k): logging.debug("difference in field %r", k)
                    logging.debug("style %r differs (self=%r, other=%r)", key, sv.as_dict(), ov.as_dict())
                    return False

            if len(self) != len(other):
                logging.debug("different # of subtitles (self=%d, other=%d)", len(self), len(other))
                return False

            for i, (se, oe) in enumerate(zip(self.events, other.events)):
                if not se.equals(oe):
                    for k in se.FIELDS:
                        if getattr(se, k) != getattr(oe, k): logging.debug("difference in field %r", k)
                    logging.debug("event %d differs (self=%r, other=%r)", i, se.as_dict(), oe.as_dict())
                    return False

            return True
        else:
            raise TypeError("Cannot compare to non-SSAFile object")