re模块
import re
# match
# 从头开始匹配, 只匹配一次,就结束
a = re.match('\d+', '54:58天5488:8451') # 默认就是0个群组
print(a.group()) # 54
a = re.match('(\d+):(\d+)', '54:58天5488:8451') # 返回一个匹配对象
print(a) # <_sre.SRE_Match object; span=(0, 5), match='54:58'>
print(a.group()) # 54:58
print(a.group(0)) # 54:58
print(a.group(1)) # 54
print(a.group(2)) # 58
# search
# 任意位置匹配,只要匹配到了一个,就结束
b = re.search('(\d+):(\d+)', '你好54:845Niha2212:5454')
print(b) # <_sre.SRE_Match object; span=(2, 8), match='54:845'>
print(b.group()) # 54:845
print(b.group(0)) # 54:845
print(b.group(1)) # 54
print(b.group(2)) # 845
# findall
# 匹配满足条件的全部内容,返回一个列表
c = re.findall('\d+', 'Niahhod5451:854jijdif8888:451nihao888')
print(c) # ['5451', '854', '8888', '451', '888']
c = re.findall('(\d+):(\d+)', 'Niahhod5451:854jijdif8888:451nihao888')
print(c) # [('5451', '854'), ('8888', '451')]
c = re.findall('\d+:\d+', 'Niahhod5451:854jijdif8888:451')
print(c) # ['5451:854', '8888:451']