Replacement of Method has_key in Python3

Question

I want to change this

def has_class_but_no_id(tag):
    return tag.has_key('class') and not tag.has_key('id')

This function is from Python2 not for Python3

I had idea that

I changed this HTML document in a list like this

list_of_descendants = list(soup.descendants)

So I can get tags which contain class but don't id it is about that find all tags with class = blabla... but not id = .... I have no idea how I can handle this problem

Keyur Potdar · Answer 1 · 2018-04-06T07:28:30.190

0

The documentation says:

I renamed one method for compatibility with Python 3:

Tag.has_key() -> Tag.has_attr()

Also, the exact same function is available in the documentation here:

If none of the other matches work for you, define a function that takes an element as its only argument. The function should return True if the argument matches, and False otherwise.

Here’s a function that returns True if a tag defines the “class” attribute but doesn’t define the “id” attribute:
def has_class_but_no_id(tag):
    return tag.has_attr('class') and not tag.has_attr('id')

edited Apr 06 '18 at 07:28

answered Apr 06 '18 at 06:33

Keyur Potdar

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ok i used ur suggestions, but there were another problem AttributeError: 'NavigableString' object has no attribute 'has_attr' like i said i changes all Tag_elements in Beautifulsoup as a List and i applied that has_attr but that error message came out can u plz advice me more? – Tae Apr 06 '18 at 08:46
You're using the function on text (NavigableString) as well as tags. using `.has_attr` on text will raise the above error. Before calling the function, check if the list item is a tag. You can use `isinstance(item, Tag)` for that. Also, don't forget to import Tag from bs4 module. – Keyur Potdar Apr 06 '18 at 09:24
If you can't implement that, add the code you're trying, in the question and I'll edit my answer accordingly. – Keyur Potdar Apr 06 '18 at 09:52

score -1 · Accepted Answer · edited Apr 08 '18 at 17:53

Hey i solve this Problem.

What i had to do is

1.collect all the tags(BeautifulSoup) and all children of tags (contents)

soup = BeautifulSoup(html_doc,"html.parser")
list_of_descendants = list(soup.descendants)

2.eliminate all NavigableStrings(cuz they can't accept has_attr() Methodes)

def terminate_navis(list_of_some):

    new_list = []

    for elem in list_of_some:

        if type(elem) == bs4.element.Tag:
            new_list.append(elem)
        else :
            continue

    return new_list 


new_list = terminate_navis(list_of_descendants)


def contents_adding(arg_list):
//this Method helps that get all the childrens of tags in lists again

    new_list = arg_list

    child_list = []

    for elem in arg_list:

        if elem.contents:

            child_list = elem.contents
            child_list = terminate_navis(child_list)
            new_list.extend(child_list)

        new_list = list(set(new_list))

    return new_list

3.filter all tags if they have attribute 'class' (has_attr) and if they don't have 'id'(also with has_attr)

def justcl(tag_lists):

    class_lists = []

    for elem in tag_lists:
        if elem.has_attr('class'):
            class_lists.append(elem)
        else :
            continue

    return class_lists

def notids(class_lists):

    no_id_lists = []

    for elem in class_lists:

        if elem.has_attr('id'):
            continue
        else :
            no_id_lists.append(elem)

    return no_id_lists

all this collected tags create as a list and print on the screen

print or using for loop and so on...

Can you please format all the code in your answer and update your question with what you want to accomplish. Specifically, with the example. I doubt you need all this messy code from your answer to achieve your goal. — radzak, Apr 07 '18 at 19:52

Replacement of Method has_key in Python3

2 Answers2