How to split the elements of strings in a list (Python)

Unfortunately we can't use assignments in list comprehensions, so this needs to be done in an explicit for loop (if we don't want to call .split and iterate 3 times)

li = ['\n                Belgium,                Female,            18- 24           ',
      '\n                Belgium,                Male,              18-24            ']

li = [elem.split() for elem in li]
print(li)
# [['Belgium,', 'Female,', '18-24'], ['Belgium,', 'Male,', '18-24']]
countries, genders, ages = [], [], []
for elem in li:
    countries.append(elem[0])
    genders.append(elem[1])
    ages.append(elem[2])

print(countries)
print(genders)
print(ages)
# ['Belgium,', 'Belgium,']
# ['Female,', 'Male,']
# ['18-24', '18-24']

Something like this, using split and filtering empty strings.

mylist = [x.strip() for x in reviewerdetails.split(" ") if len(x.strip()) > 0];

Try using list comprehensions:

output = [input[i].split( do whatever you need to in here ) for i in range(len(input))]

The split function is a member of string, not list, so you need to apply the function to each element in the list, not to the list itself.

Hope i understood correctly, I think this is what you are trying to do:

main_list = [
    '\n                Belgium,                Female,                18-24            ',
    '\n                Belgium,                Female,                18-24            '
]
for s in main_list:
    # create a list split by comma
    sub_list = s.split(",")
    # cleanup any whitespace from each list item
    sub_list = [x.strip() for x in sub_list]
    print(sub_list)

I am also a new programmer to Python, so this might be inefficient. The way I would do it would be to have three lists, one for the country, one for the gender, and one for the age range. Then I would do for loops, so if the countries list has [...,'Belgium',...] in it, it would know. So for each list, I would say

for reviewer in reveiwerdetails:
    for country in [country list name]:
        if country in reviewer:
            [list name].append(country)
            break
    for gender in [gender list name]:
        if gender in reviewer:
            [list name].append(gender)
            break
    for agerange in [age range list name]:
        if agerange in reviewer:
            [list name].append(agerange)
            break

So that way you have a list with all the countries of the reviewers, genders, and age ranges in order. Again, this is probably extremely inefficient and there are most likely much easier ways of doing it.