将分隔的字段合并为一个

fields = ['field1', 'field2', 'field3']  # 分隔的字段列表
delimiter = ','  # 分隔符

merged_string = ''  # 合并后的字符串

for field in fields:
    merged_string += field + delimiter

# 去除最后一个分隔符
merged_string = merged_string.rstrip(delimiter)

print(merged_string)