import re
p = re.compile(r'^(\d+)\s[^(]+\(([^()]+)\)')
test_str = "70849 mozilla/5.0(linux;u;android4.2.1;zh-cn)applewebkit/534.30(khtml,likegecko)version/4.0mobilesafari/534.30"
print(p.findall(test_str))
# or using re.search if the number is not at the beginning of the string
m = re.search(r'(\d+)\s[^(]+\(([^()]+)\)', test_str)
if m:
print("Number: {0}\nString: {1}".format(m.group(1), m.group(2)))
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