I have some object.ID-s which I try to store in the user session as tuple. When I add first one it works but tuple looks like [u'2',] but when I try to add new one using mytuple = mytuple + new.id got error can only concatenate tuple [not "unicode"] to tuple.
Tomerikoo
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asked May 24, 2013 at 8:04
You need to make the second element a 1-tuple, eg:
a = ['2',]
b = 'z'
new = a + [b,]
answered May 24, 2013 at 8:05
Jon Clements♦Jon Clements
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Since Python 3.5 [PEP 448] you can do unpacking within a tuple, list set, and dict:
a = ['2',]
b = 'z'
new = [*a, b]
answered Aug 28, 2016 at 15:56
nitelynitely
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From tuple to list to tuple :
a = ['2',]
b = 'b'
l = list[a]
l.append[b]
tuple[l]
Or with a longer list of items to append
a = ['2',]
items = ['o', 'k', 'd', 'o']
l = list[a]
for x in items:
l.append[x]
print tuple[l]
gives you
>>>
['2', 'o', 'k', 'd', 'o']
The point here is: List is a mutable sequence type. So you can change a given list by adding or removing elements. Tuple is an immutable sequence type. You can't change a tuple. So you have to create a new one.
modesto
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answered May 24, 2013 at 8:22
kiriloffkiriloff
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Tuple can only allow adding tuple to it. The best way to do it is:
mytuple =[u'2',]
mytuple +=[new.id,]
I tried the same scenario with the below data it all seems to be working fine.
>>> mytuple = [u'2',]
>>> mytuple += ['example text',]
>>> print mytuple
[u'2','example text']
julienc
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answered Jul 2, 2014 at 15:25
>>> x = [u'2',]
>>> x += u"random string"
Traceback [most recent call last]:
File "", line 1, in
x += u"random string"
TypeError: can only concatenate tuple [not "unicode"] to tuple
>>> x += [u"random string", ] # concatenate a one-tuple instead
>>> x
[u'2', u'random string']
answered May 24, 2013 at 8:05
jamylakjamylak
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0
#1 form
a = ['x', 'y']
b = a + ['z',]
print[b]
#2 form
a = ['x', 'y']
b = a + tuple['b']
print[b]
answered Aug 18, 2017 at 16:27
britodfbrbritodfbr
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1
Bottom line, the easiest way to append to a tuple is to enclose the element being added with parentheses and a comma.
t = ['a', 4, 'string']
t = t + [5.0,]
print[t]
out: ['a', 4, 'string', 5.0]
answered Feb 7, 2020 at 5:20
If the comma bugs you, you can specify it's a tuple using tuple[].
ex_tuple = ['a', 'b']
ex_tuple += tuple['c']
print[ex_tuple]
answered 18 hours ago
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