Python Day-Objectionpiended编程（OOPS），CSV，Matplotlib

from PIL import Image
photo = Image.open("abcd.jpeg")
photo.show()

import matplotlib.pyplot as plt
import csv

years = []
sales = []
with open("sales.csv", "r") as f:
    reader = csv.reader(f)
    next(reader)  # 跳过表头
    for row in reader:
        years.append(int(row[0]))
        sales.append(int(row[1]))

plt.figure(figsize=(7, 5))
plt.plot(years, sales, color="r", label="Yearly Sales")
plt.xlabel('Years')
plt.ylabel("Sales")
plt.title("Last 5 Years Sales")
plt.legend() # 添加图例
plt.show()

f = open("abcd.txt", "w")
print(type(f))
print(f.name)
print(f.mode)
print(f.readable())
print(f.writable())
print(f.closed)
f.close()

f = open("abcd.txt", "w")
f.write("friday\nsaturday\n") # 使用 \n 换行
f.close()

f = open("abcd.txt", "a")
f.write("sunday\nmonday\n")
f.close()

f = open("abcd.txt", "r")
data = f.read()
print(data)
f.close()

f = open("abcd.txt", "r")
data = f.read(5) # 读取前5个字符
print(data)
f.close()

f = open("abcd.txt", "r")
line = f.readline() # 读取一行
print(line)
f.close()

f = open("abcd.txt", "r")
lines = f.readlines() # 读取所有行到列表
for line in lines:
    print(line, end="")
f.close()

f = open("abcd.txt", "r")
data = f.readlines()

num_lines = len(data)
num_words = 0
num_letters = 0
for line in data:
    words = line.split()
    num_words += len(words)
    for word in words:
        num_letters += len(word)

f.close()
print(f"Number of lines: {num_lines}")
print(f"Number of words: {num_words}")
print(f"Number of letters: {num_letters}")

import os
file_name = input("Enter file name: ")
if os.path.isfile(file_name):
    print("File is present")
else:
    print("File is not present")