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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 get_transactions_csv(self, include_investment=False, acct=0):
 """Returns the raw CSV transaction data as downloaded from Mint. If include_investment == True, also includes transactions that Mint classifies as investment-related. You may find that the investment transaction data is not sufficiently detailed to actually be useful, however. """


        # Specifying accountId=0 causes Mint to return investment
        # transactions as well.  Otherwise they are skipped by
        # default.
        params = None
        if include_investment or acct > 0:
            params = {'accountId': acct}
        result = self.request_and_check(
            '{}/transactionDownload.event'.format(MINT_ROOT_URL),
            params=params,
            expected_content_type='text/csv')
        return result.content