PROGRAMMING:Change the upper case letters in the string to lower case letters

Change the uppercase letter in the string to lowercase letter, other characters remain unchanged.
###Input format:
Enter a string of no more than 20 in length that contains uppercase, lowercase and digits.
###Output format:
Output the string after changing the upper case letter to lower case letter.
###Input example:
```in
Here is a set of inputs. For example:
abcAZ123
```
###Output example:
```out
The corresponding output is given here. For example:
abcaz123
```






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