Matplotlib, переключение между графиками

import codecs
import matplotlib.pyplot as plt
import numpy as np
nbook = "Book 1 - The Philosopher_s Stone.txt"
def uno(nbook):
    names = open('Имена.txt')
    notzeros = 0
    lnames = names.readlines()
 
    for i in range (len(lnames)):
        lnames[i] = lnames[i].strip()
    names.close()
    mnames = [0] * len(lnames)
        
    book = codecs.open(nbook, "r", "utf-8")
    text = book.read()
 
    for i in range (len(lnames)):
        if lnames[i] in text:
            mnams = mnames[i]
            mnams += text.count(lnames[i])
            mnames[i] = mnams
            
    for i in range (len(lnames)):
        if mnames[i] > 10:
            notzeros += 1
       
    amnames = [0] * notzeros
    alnames = [0] * notzeros   
    k=-1
    for i in range (len(lnames)):
        if mnames[i] > 10:
            k += 1
            amnames[k] = mnames[i]
            alnames[k] = lnames[i]
    
    fig = plt.figure(figsize=(10,10))
    plt.barh(alnames, amnames)
    plt.title("Mentions")
 
uno("Book 1 - The Philosopher_s Stone.txt")
uno("Book 2 - The Chamber of Secrets.txt")
uno("Book 3 - The Prisoner of Azkaban.txt")
uno("Book 4 - The Goblet of Fire.txt")
uno("Book 5 - The Order of the Phoenix.txt")
uno("Book 6 - The Half Blood Prince.txt")
uno("Book 7 - The Deathly Hallows.txt")
 
plt.show()