### StringIO

```

from io import StringIO


def meth1(string):
    a = []
    for i in range(100):
        a.append(string)
    return ''.join(a)

def meth2(string):
    a = StringIO()
    for i in range(100):
        a.write(string)
    return a.getvalue()


if __name__ == '__main__':
    from timeit import Timer
    string = "This is test string"
    print(Timer("meth1(string)", "from __main__ import meth1, string").timeit())
    print(Timer("meth2(string)", "from __main__ import meth2, string").timeit())

```