PROGRAMMING:Calculate the sum of 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9

Write a program to calculate the sum of 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9.
###Input format:
No input
###Output format:
1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 = calculation sum
###Input example:
```in
```
###Output example:
```out
1+2+3+4+5+6+7+8+9= 45
```






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