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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 find_emails_by_subject(self, subject, limit=50, match_recipient=None):
 """ Searches for Email by Subject. Returns email's imap message IDs as a list if matching subjects is found. Args: subject (str) - Subject to search for. Kwargs: limit (int) - Limit search to X number of matches, default 50 match_recipient (str) - Recipient to exactly (don't care if not specified) Returns: list - List of Integers representing imap message UIDs. """

        # Select inbox to fetch the latest mail on server.
        self._mail.select("inbox")

        matching_uids = self.__search_email_by_subject(
            subject, match_recipient)

        return matching_uids