<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_string(self):
 """ Get file format as string :return: String describing the file format :rtype: str """

        if self in [MimeType.TIFF_d8, MimeType.TIFF_d16, MimeType.TIFF_d32f]:
            return 'image/{}'.format(self.value)
        if self is MimeType.JP2:
            return 'image/jpeg2000'
        if self in [MimeType.RAW, MimeType.REQUESTS_RESPONSE]:
            return self.value
        return mimetypes.types_map['.' + self.value]