Each address should start with '0x' followed by 40 hexadecimal characters.
Examples
Valid:
0x0000000000000000000000000000000000000000, 0x1234567890abcdefABCDEF1234567890abcdefAB
Invalid: 0x123, 1234567890abcdefABCDEF1234567890abcdefAB, 0xG234567890abcdefABCDEF1234567890abcdefAB,
0x1234567890abcdefABCDEF1234567890abcdefABCD