如何让Python将素数打印到文本文件中？
这个问题在这里已经有了答案：
fo = open('primes.txt', 'w') #tells python to open the file and delete everything in it
也许你想要
fo = open('primes.txt', 'a') # tells python to append to the file
真的，你不应该这样做，你应该用它来安全地打开你的文件，并且只在循环之外进行一次
with open("primes.txt","w") as fo:
for n in range (x,y):
if all(n%i!=0 for i in range (2,n)):
a=[]
a.append(n)
print (">>>Writing the values to primes.txt...")
print ("##########Calculated by my prime calculator##########", file = fo)
print ("", file = fo)
print ((a), file = fo)