Python Traceback TypeError：＆＃39; str＆＃39;对象不可调用

Question

当我运行此代码时：

def printPredictions(matches):
    pPredictionTable = PrettyTable()
    pPredictionTable.field_names = ["Player 1", "Player 2", "Difference", "Winner"]
    for match in matches:
        p1 = match['teamA']
        p2 = match['teamB']
        if match['aBeatb'] == True:
            pPredictionTable.add_row([match['teamA'], match['teamB'], match['difference'], p1])             
        else:
            pPredictionTable.add_row([match['teamA'], match['teamB'], match['difference'], p2])

    print(pPredictionTable)    

printPredictions(pmatches)

我收到此错误：

Traceback (most recent call last):
  File "C:\Users\ericr_000\Desktop\PyDev\NPA-2-Rating-System\Rankings.py", line 645, in <module>
    printPredictions()
TypeError: 'str' object is not callable

我将pmatches作为单独的词典，而且我没有编码技巧来解决这个问题。 （第145行是printPredictions（匹配）