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Gilbert Craig
2,102 PointsClassmethod contruction challenge - stumped
I am definitely stuck with this one ..... Any pointer greatly appreciated
@classmethod
def from_string(cls, string):
answer = []
for char in string:
if char == 'dot':
answer.append('.')
elif char == 'dash':
answer.append('_')
return cls('-'.join(answer))
1 Answer

Jeff Muday
Treehouse Moderator 27,510 PointsYou are very close! I can see you understood the concept pretty well.
I fixed the code and commented the lines where changes should take place.
Think of 'dot' and 'dash' as tokens in a string where tokens are separated by hyphens rather than thinking of the string in terms of a string iterable.
So... we create a LIST called tokens, which we split on the hyphens '-'... then your code will work. Also, the question wanted a LIST to be returned -- you built the list correctly as 'answer' -- so rather than joining it again to be a single string, just return the list.
Good luck with Python, it is worth the effort!
@classmethod
def from_string(cls, string):
answer = []
tokens = string.split('-') # ADD THIS
for char in tokens: # CHANGE ITERABLE to TOKENS LIST
if char == 'dot':
answer.append('.')
elif char == 'dash':
answer.append('_')
return cls(answer) # RETURN THE LIST ANSWER RATHER THAN JOINING
Gilbert Craig
2,102 PointsGilbert Craig
2,102 PointsThanks Jeff for the comprehensive answer