Creating a function that purges content of a group of lists using python-CodePudding

I have a group of lists

embed_list = []
hreflist = []
nationality_list = []
Movie_NAMEnYEAR_strap_list = []
actors_list=[]
poster_url = []
list_of_genres = []

and after adding some strings to them, I want to purge them, so I tried the following

1st I tried using .clear() but I got the following error

'str' object has no attribute 'clear'

then I tried re-initiating the list value to [] using a function

def purging_lists():
    
    embed_list = []
    hreflist = []
    nationality_list = []
    Movie_NAMEnYEAR_strap_list = []
    actors_list=[]
    poster_url = []
    list_of_genres = []

but it wasn't effective

CodePudding user response：

The clear method should work fine for your purpose. Just make sure to apply it to the whole list, not individual items. For example:

actors_list = []
actors_list.append('Jeff Bridges')
actors_list.append('John Goodman')
print(actors_list)  # Output: ['Jeff Bridges', 'John Goodman']

# Wrong:
actors_list[0].clear()  
# AttributeError: 'str' object has no attribute 'clear'

# Right:
actors_list.clear()
print(actors_list)  # Output: []

Your function did not have the desired effect, because you created empty lists as new local variables inside the function, rather than overwriting the existing lists. To make this idea work, you would have to declare that you are referring to the lists that exist outside the function, using the global statement, e.g.:

def purging_lists():
    global actors_list  
    actors_list = []

But that is unnecessarily convoluted. Just use list.clear(), as outlined above.