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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 results_tc(self, key, value):
 """Write data to results_tc file in TcEX specified directory. The TcEx platform support persistent values between executions of the App. This method will store the values for TC to read and put into the Database. Args: key (string):
 The data key to be stored. value (string):
 The data value to be stored. """

        if os.access(self.default_args.tc_out_path, os.W_OK):
            results_file = '{}/results.tc'.format(self.default_args.tc_out_path)
        else:
            results_file = 'results.tc'

        new = True
        open(results_file, 'a').close()  # ensure file exists
        with open(results_file, 'r+') as fh:
            results = ''
            for line in fh.read().strip().split('\n'):
                if not line:
                    continue
                try:
                    k, v = line.split(' = ')
                except ValueError:
                    # handle null/empty value (e.g., "name =")
                    k, v = line.split(' =')
                if k == key:
                    v = value
                    new = False
                if v is not None:
                    results += '{} = {}\n'.format(k, v)
            if new and value is not None:  # indicates the key/value pair didn't already exist
                results += '{} = {}\n'.format(key, value)
            fh.seek(0)
            fh.write(results)
            fh.truncate()