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Alex Rosier
Courses Plus Student 648 PointsI am using the type() function to identify data types in list and remove by type. Why does this fail for inner list?
messy_list = ["a", 2, 3, 1, False, [1, 2, 3]]
Your code goes below here
messy_list.insert(0, messy_list.pop(3))
for item in messy_list: if type(item) is str: messy_list.remove(item) elif type(item) is bool: messy_list.remove(item) # Why does the below fail to execute? elif type(item) is list: messy_list.remove(item) else: pass
messy_list = ["a", 2, 3, 1, False, [1, 2, 3]]
# Your code goes below here
messy_list.insert(0, messy_list.pop(3))
for item in messy_list:
if type(item) is str:
messy_list.remove(item)
elif type(item) is bool:
messy_list.remove(item)
# Why does the below fail to execute?
elif type(item) is list:
messy_list.remove(item)
else:
pass
1 Answer
Steven Parker
231,269 PointsRemoving items from an iterable while it is controlling a loop can cause other items to be skipped. To avoid this, you can use a copy of the iterable to control the loop.
Also, you can simplify things by removing anything that's not what you want instead of each explicit other type:
for item in messy_list.copy():
if type(item) is not int:
messy_list.remove(item)