怎么把运行出来的图表纵横坐标转换啊！

怎样把运行出来的图表纵横的坐标进行转换啊！或者怎么把图表实线变成虚线。

给个例子你参考一下吧：

from random import randint
from matplotlib import pyplot as plt
import pandas as pd
import numpy as np
mouth = np.arange(1,13)
df = pd.DataFrame()
df.index = mouth
df['货号1'] = [randint(1000,10000) for i in range(len(mouth))]
df['货号2'] = [randint(1000,10000) for i in range(len(mouth))]
df['货号3'] = [randint(1000,10000) for i in range(len(mouth))]
df['货号4'] = [randint(1000,10000) for i in range(len(mouth))]
df['货号5'] = [randint(1000,10000) for i in range(len(mouth))]
df['货号6'] = [randint(1000,10000) for i in range(len(mouth))]
print(df)
plt.rcParams['axes.unicode_minus']=False
plt.rcParams['font.sans-serif']=['SimHei']
# df.plot()
plt.plot(df['货号1'],mouth)
plt.plot(df['货号2'],mouth)
plt.plot(df['货号3'],mouth)
plt.plot(df['货号4'],mouth)
plt.plot(df['货号5'],mouth)
plt.plot(df['货号6'],mouth)
plt.show()