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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 _write_field(self, value):
 """ Write a single field to the destination file. :param T value: The value of the field. """

        class_name = str(value.__class__)
        if class_name not in self.handlers:
            raise ValueError('No handler has been registered for class: {0!s}'.format(class_name))
        handler = self.handlers[class_name]
        handler(value, self._file)