Python seek和tell

f = open("胡辣汤", mode="r+", encoding="utf-8")
f.seek(0,2) # 移动到末尾
content = f.read(5)
print(content)
f.seek(0) # 移动到开头
print(f.read())
print(f.tell())  # 字节
#
f.seek(3)
print(f.read())