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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 to_json(self, value, preserve_ro):
 """ Returns the JSON encoding of the given attribute value. If the value has a 'to_json_dict' object, that method is called. Otherwise, the following values are returned for each input type: - datetime.datetime: string with the API representation of a date. - dictionary: if 'atype' is ApiConfig, a list of ApiConfig objects. - python list: python list (or ApiList) with JSON encoding of items - the raw value otherwise """

    if hasattr(value, 'to_json_dict'):
      return value.to_json_dict(preserve_ro)
    elif isinstance(value, dict) and self._atype == ApiConfig:
      return config_to_api_list(value)
    elif isinstance(value, datetime.datetime):
      return value.strftime(self.DATE_FMT)
    elif isinstance(value, list) or isinstance(value, tuple):
      if self._is_api_list:
        return ApiList(value).to_json_dict()
      else:
        return [ self.to_json(x, preserve_ro) for x in value ]
    else:
      return value