用python对字符串按固定长度连续进行分割

with open("常用1500字.txt",encoding='utf-8')as f:
    content = f.read()
    n_content = content[:]
    list1 = []
    while True:
        aim_file = n_content[:50]
        list1.append(aim_file)
        n_content = n_content.strip(aim_file)
        if len(n_content)==0:
            break
    with open("practice.txt","w")as fa:
        for i in list1:
            fa.write(i+"\n")