Write a C function to set bit7 (bit counts from the right to left as bit0, bit1, bit2, bit3, bit4, bit5, bit6, bit7, ) in an unsigned integer number, and return the converted unsigned number.

The function prototype is as follows,

unsigned int set_bit7(unsigned int n);

/* set bit7 of n to 1 and keep the remaining bits unchanged, and return the result to the function. */

For example, a function call like set_bit7(127) will return 255, while set_bit7(0) will return 128