import re
pnumber = re.sub("[^0-9]", "", '(510) 757-5030') #替换非数字字符
if len(pnumber) < 10:  #小于10位数不是电话号码
    pass
else:
    if pnumber[0] == '1':
        pnumber = pnumber[1:]#strip 1st char if it's a 1  #去掉首位是1的电话
    if len(pnumber) == 10:
        pnumber = "+1 %s-%s-%s" % (pnumber[:3],pnumber[3:6],pnumber[6:]) #统一格式
    else:
        pass
print(pnumber)