Python: parse gdb.value to bytearray

I try to parse an char[] / char* from gdb.value to bytearray or a list of ints etc.

following test code in c:

int main(int argc, char *argv[])
{

    char img[] = {0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF,
                  0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00,
                  0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF};

    char* imgp = img;
    return 0;
}

first try:

v = gdb.parse_and_eval("img")
print(v)
l = list(bytearray(v))

output:

~"\"\\377\\000\\377\\000\\377\\000\\377\\000\\377\\000\\377\\000\\377\\000\\377\\000\\377\\000\\377\\000\\377\\000\\377\\000\\377\\000\\377\"\n"
TypeError: 'gdb.Value' object is not iterable\n"

yay a string!? no gdb.value -> not iterable :( but index able ... ok

data = []
for i in range(0, 27):
   data.append(int(v[i]))

result:

Python Exception <class 'gdb.MemoryError'> Cannot access memory at address 0x7ffc737be000:

ok lets do it the "safe" way:

 v = gdb.parse_and_eval("img") 
 inferior = gdb.selected_inferior()
 mem = inferior.read_memory(v, 27)

result:

Python Exception <class 'gdb.MemoryError'> Cannot access memory at address 0x7ffc737be000:

Okay whats wrong? How do I get this data out of the gdb.value type?