How to fill in a dictionary with key and value from a string?

[C W]

A different but related question:

myDict = dict(zip(string.ascii_lowercase + string.ascii_uppercase,
string.ascii_lowercase + string.ascii_uppercase))
>myDict
{'A': 'A', 'B': 'B', 'C': 'C',...,'w': 'w', 'x': 'x', 'y': 'y', 'z': 'z'}

Why are the keys sorted from upper case to lower case? I asked for lower
case first, then upper case.



On Sun, Apr 1, 2018 at 8:52 PM, C W <tmrsg11 at gmail.com> wrote:

> Thank you all for the response.
>
> What if I have myDict = {'a': 'B', 'b': 'C',...,'z':'A' }? So now, the
> values are shift by one position.
>
> key:    abcdefghijklmnopqrstuvwxyz
> value: BCDEFGHIJKLMNOPQRSTUVWXYZA
>
> Can I fill in a key and its corresponding value simultaneously on the fly?
>
> Something in the following structure.
>
> myDict = {}
> for i in range(26):
>        myDict[lowercase] = uppercase
>
> Thank you!
>
> On Sun, Apr 1, 2018 at 1:13 PM, Chris Angelico <rosuav at gmail.com> wrote:
>
>> On Mon, Apr 2, 2018 at 3:03 AM, Rustom Mody <rustompmody at gmail.com>
>> wrote:
>> > On Saturday, March 31, 2018 at 4:30:04 PM UTC+5:30, bartc wrote:
>> >> On 30/03/2018 21:13, C W wrote:
>> >> > Hello all,
>> >> >
>> >> > I want to create a dictionary.
>> >> >
>> >> > The keys are 26 lowercase letters. The values are 26 uppercase
>> letters.
>> >> >
>> >> > The output should look like:
>> >> > {'a': 'A', 'b': 'B',...,'z':'Z' }
>> >>
>> >> > I know I can use string.ascii_lowercase and string.ascii_uppercase,
>> but how
>> >> > do I use it exactly?
>> >> > I have tried the following to create the keys:
>> >> > myDict = {}
>> >> >          for e in string.ascii_lowercase:
>> >> >              myDict[e]=0
>> >>
>> >> If the input string S is "cat" and the desired output is {'c':'C',
>> >> 'a':'A', 't':'T'}, then the loop might look like this:
>> >>
>> >>     D = {}
>> >>     for c in S:
>> >>         D[c] = c.upper()
>> >>
>> >>     print (D)
>> >>
>> >> Output:
>> >>
>> >> {'c': 'C', 'a': 'A', 't': 'T'}
>> >
>> > As does…
>> >>>> {c: c.upper() for c in s}
>> > {'a': 'A', 'c': 'C', 't': 'T'} : dict
>> >
>> > [Recent pythons; not sure when dict-comprehensions appeared]
>>
>> 3.0, and also backported to 2.7. So go ahead and use 'em.
>>
>> https://www.python.org/dev/peps/pep-0274/
>>
>> ChrisA
>> --
>> https://mail.python.org/mailman/listinfo/python-list
>>
>
>