使用 PyInputPlus 将字符串限制为特定长度并仅允许某些字符

Question

how do I use PyInputPlus to restrict input length and it's allowed characters. I did some research and found this question , but this question doesn't have answer specifically for PyInputPlus. And I want to allow both 'az' and 'A-Z'.

Code so far:

import pyinputplus as pyip
oneLetter = pyip.inputStr(prompt=':')
if not re.match("^[a-z]*$", letter):
   print ("Error! Only letters a-z allowed!")
if len(letter)>1:
   print('You can only type in 1 character')
else:
   print(oneLetter)

Desire output:

:1
>Only letters a-z, A-Z allowed
:Bob
>Only 1 letter allowed
:B
>B

Answer 1

You may try the code below to fix your issue. I would suggest getting more familiar with regular expressions.

import pyinputplus as pyip
import regex as re

oneLetter = pyip.inputStr(prompt=':')
if len(oneLetter) > 1:
   print('You can only type in 1 character')
elif not re.match("^[a-zA-Z]$", oneLetter):
   print ("Error! Only letters a-z allowed!")
else:
   print(oneLetter)