code: def get_doc(additional_doc=False,
              field_prefix='$',
              field_suffix=':',
              indent=4):
      
      if additional_doc:
          f = fields.copy()
          f.update(additional_doc)
      else:
          f = fields
      field_length = get_max_field_length(f)
      field_length = field_length + len(field_prefix) + len(field_suffix) + 4
      description_indent = ' ' * (indent + field_length)
      output = ''
      for field, description in sorted(f.items()):
          description = description['description']
          field = ' ' * indent + field_prefix + field + ':'
          output += field.ljust(field_length) + \
              textwrap.fill(
                  description,
                  width=78,
                  initial_indent=description_indent,
                  subsequent_indent=description_indent
              )[field_length:] + '\n\n\n'
  
      return output
docs: Return a formated string containing documentation about the audio
      fields.