code: def get_fills(self, product_id=None, order_id=None, **kwargs):
          
          if (product_id is None) and (order_id is None):
              raise ValueError('Either product_id or order_id must be specified.')
  
          params = {}
          if product_id:
              params['product_id'] = product_id
          if order_id:
              params['order_id'] = order_id
          params.update(kwargs)
  
          return self._send_paginated_message('/fills', params=params)
docs: Get a list of recent fills.
  
          As of 8/23/18 - Requests without either order_id or product_id
          will be rejected
  
          This method returns a generator which may make multiple HTTP requests
          while iterating through it.
  
          Fees are recorded in two stages. Immediately after the matching
          engine completes a match, the fill is inserted into our
          datastore. Once the fill is recorded, a settlement process will
          settle the fill and credit both trading counterparties.
  
          The 'fee' field indicates the fees charged for this fill.
  
          The 'liquidity' field indicates if the fill was the result of a
          liquidity provider or liquidity taker. M indicates Maker and T
          indicates Taker.
  
          Args:
              product_id (str): Limit list to this product_id
              order_id (str): Limit list to this order_id
              kwargs (dict): Additional HTTP request parameters.
  
          Returns:
              list: Containing information on fills. Example::
                  [
                      {
                          "trade_id": 74,
                          "product_id": "BTC-USD",
                          "price": "10.00",
                          "size": "0.01",
                          "order_id": "d50ec984-77a8-460a-b958-66f114b0de9b",
                          "created_at": "2014-11-07T22:19:28.578544Z",
                          "liquidity": "T",
                          "fee": "0.00025",
                          "settled": true,
                          "side": "buy"
                      },
                      {
                          ...
                      }
                  ]