import re
b=r'C:\Users\noname\PycharmProjects\untitled29\test\1.txt:b6ab66c58253a0f21931c1def7898859'
a=re.compile(':(\w+)')
print a.findall(b)

 import re
b=r'C:\Users\noname\PycharmProjects\untitled29\test\1.txt:b6ab66c58253a0f21931c1def7898859'
a=re.compile(':(\w+)')
hash_md = a.findall(b)[0]
path = b[:-(len(hash_md)+1)]
print(path, hash_md)

  
>>> s = (r'C:\Users\noname\PycharmProjects'
...      r'\untitled29\test\1.txt:b6ab66c58253a0f21931c1def7898859')
>>> 
>>> out = s.rsplit(':', 1)
>>> out
['C:\\Users\\noname\\PycharmProjects\\untitled29\\test\\1.txt', 'b6ab66c58253a0f21931c1def7898859']
>>>

  
>>> import re
>>> 
>>> s = (r'C:\Users\noname\PycharmProjects'
...      r'\untitled29\test\1.txt:b6ab66c58253a0f21931c1def7898859')
>>> 
>>> out = re.search(r'(.*):(.*)$', s).groups()
>>> out
('C:\\Users\\noname\\PycharmProjects\\untitled29\\test\\1.txt', 'b6ab66c58253a0f21931c1def7898859')
>>>