wkt
123456789101112131415161718192021222324252627282930313233343536373839
# encoding: utf-8
import re
s1="""
121.651677477117
31.3356535990687
121.651671441881
31.3356569230189
121.651396002163
31.3356039288364
121.651349940836
31.33554112919
121.651262186142
31.3354189904255
121.651327310333
31.3351837898146
121.651366550272
31.3351628153179
121.651541910089
31.3350677693326
121.651814307072
31.335121072928
121.651953163705
31.3353058556916
121.651886645654
31.335539361219
121.651778519457
31.335598193999
121.651677477117
31.3356535990687
"""
split = '([\s\S]*?)'
pattern = '(121\.\d+' + split + '31\.\d+)'
res = re.findall(pattern, s1)
# points = [re.sub(split, ' ', item[0]) for item in res]
points =[item[0].replace(item[1], ' ') for item in res]
print('POLYGON ((%s))' % ','.join(points))
points = [item[0].replace(item[1], ',') for item in res]
print('IECS %s' % ' '.join(points))
Python
INFO