如何获得数组中每个项目在所有文档中出现的次数之和？

def get_total_occurrences(arr, documents):
    occurrences = {}
    
    # 统计每个项目在数组中的出现次数
    for item in arr:
        if item in occurrences:
            occurrences[item] += 1
        else:
            occurrences[item] = 1
    
    # 遍历所有文档，将每个文档中的数组进行处理
    for doc in documents:
        for item in doc:
            if item in occurrences:
                occurrences[item] += 1
            else:
                occurrences[item] = 1
    
    # 计算所有项目的出现次数之和
    total_occurrences = sum(occurrences.values())
    
    return total_occurrences