import re
str = 'We four guys, live at 2nd street of Malibeu 521. I had a cash of $248 in my pocket. I got a ticket with serial number 88796451-52.'
#search using regex
x = re.findall('[0-9]+', str)
print('All Numbers
',x)
#digits of length N
N=3
def filterNumber(n):
if(len(n)==N):
return True
else:
return False
#filter the list
finalx = list(filter(filterNumber, x))
print('Final List
',finalx)