在Python 2.7中转换2D列表中的字符串字符

# 原始的2D列表
original_list = [['a', 'b', 'c'], ['d', 'e', 'f'], ['g', 'h', 'i']]

# 要替换的字符和目标字符
old_char = 'a'
new_char = 'x'

# 使用列表推导式和replace()方法转换2D列表中的字符串字符
new_list = [[element.replace(old_char, new_char) for element in sublist] for sublist in original_list]

# 打印转换后的2D列表
print(new_list)

[['x', 'b', 'c'], ['d', 'e', 'f'], ['g', 'h', 'i']]