If you see here "Tuples and Sequences" you can see that your data structure is a tuple.

You can see here "More on Lists" that sort() is a function only for arrays.

You can use sorted() to sort arrays or tuples

new_list=("a","g","x","e","s","s")   
a=sorted(new_list) # ['a', 'e', 'g', 's', 's', 'x']

You're getting a tuple returned, not a list. You can't just matches.sort(...) that.

OpenCV, since v4.5.4, exhibits this behavior in its Python bindings generation.

You have to use this instead:

matches = sorted(matches, ...)

This creates a new list, which contains the sorted elements of the original tuple.

Related issues:

• https://github.com/opencv/opencv/issues/21266
• https://github.com/opencv/opencv/issues/21284

If you want to use sort(), you need to convert the tuple to a list; then sort the list. Once you have sorted the list, you can convert the sorted list to a tuple. · You can also use the sorted() function to sort a tuple without converting it to a list. The sorted() function will convert the tuple to a list. · Example: · >>> t = ('cc', 'aa', 'dd', 'bb')>>> t1=list(t)>>> t1.sort()>>> tuple(t1)('aa', 'bb', 'cc', 'dd')>>> t('cc', 'aa', 'dd', 'bb')>>> sorted(t)['aa', 'bb', 'cc', 'dd']>>> tuple(sorted(t))

If you want to use sort(), you need to convert the tuple to a list; then sort the list. Once you have sorted the list, you can convert the sorted list to a tuple. · You can also use the sorted() function to sort a tuple without converting it to a list. The sorted() function will convert the tuple to a list. · Example: · >>> t = ('cc', 'aa', 'dd', 'bb')>>> t1=list(t)>>> t1.sort()>>> tuple(t1)('aa', 'bb', 'cc', 'dd')>>> t('cc', 'aa', 'dd', 'bb')>>> sorted(t)['aa', 'bb', 'cc', 'dd']>>> tuple(sorted(t))

Remove the * in front of *arg. That is converting the argument into a tuple.

You return four variables s1,s2,s3,s4 and receive them using a single variable obj. This is what is called a tuple, obj is associated with 4 values, the values of s1,s2,s3,s4. So, use index as you use in a list to get the value you want, in order.

Copyobj=list_benefits()
print obj[0] + " is a benefit of functions!"
print obj[1] + " is a benefit of functions!"
print obj[2] + " is a benefit of functions!"
print obj[3] + " is a benefit of functions!"

This error indicates that value is a tuple, and not a string as you might expect. This indicates a problem with your application.

Here the problem is that fetchone() returns a one-tuple. You should change from this line:

value = results.fetchone()

to this (notice the comma after value):

value, = results.fetchone()

or this (not recommended):

value = results.fetchone()[0]

---

But why is fetchone() returning a tuple instead of a string? Because you can SELECT multiple columns. Consider for example the following SQL statement:

SELECT a, b, c FROM my_table;

In this case, fetchone() will return a three-tuple.

Writing value, = fetchone() you are telling Python that you are expecting a one-tuple and you want that single item placed into value. If you were expecting the three-tuple, you'd have used column_a, column_b, column_c = resulsts.fetchone().

This is the reason why you should prefer value, over fetchone()[0].

---

Bonus tip: I noticed you are using Python 3. In this case, you can write:

translation_table = dict.fromkeys(b'+-(),', None)

Speeding up your code and making it more clean.

zip returns a list of tuples; you can sort them by accessing the elements with their index:

result_list.sort(key=lambda x: x[1], reverse=True)

if you like to be more explicit, you can use collections.namedtuple, and access the element via dot notation on the attribute name:

from collections import namedtuple


Poll = namedtuple('Poll', ['candidate', 'numvotes'])

uniquecandidate = ['a', 'b', 'c', 'd']
votes = [3, 4, 7, 1]

poll_results = list(map(Poll, uniquecandidate, votes))
poll_results.sort(key=lambda x: x.numvotes, reverse=True)

print(poll_results)

or with typing.NamedTuple:

from typing import NamedTuple

class Poll(NamedTuple):
    candidate: str
    numvotes: int

uniquecandidate = ['a', 'b', 'c', 'd']
votes = [3, 4, 7, 1]

poll_results = list(map(Poll, uniquecandidate, votes))
poll_results.sort(key=lambda x: x.numvotes, reverse=True)

print(poll_results)

out:

[Poll(candidate='c', numvotes=7), Poll(candidate='b', numvotes=4), Poll(candidate='a', numvotes=3), Poll(candidate='d', numvotes=1)]

items() is a method specifically for dictionaries, not tuples. Tuples are like lists, except they are immutable.