from timeit import Timer
import re
 
s = '1.2.3.4.5.6.7'
 
def f1():
    return s[:s.index('.', s.index('.')+1)]
 
def f2():
    return '.'.join(s.split('.', 2)[:2])
 
pattern = re.compile(r'^[0-9]+\.[0-9]+')
def f3():
 
    return pattern.search(s).group()
 
 
N = 100000
print(Timer(stmt='f1()', setup='from __main__ import f1').timeit(number = N))
print(Timer(stmt='f2()', setup='from __main__ import f2').timeit(number = N))
print(Timer(stmt='f3()', setup='from __main__ import f3').timeit(number = N))
print f1()
print f2()
print f3()

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