SQUARE WITH UPPER LEFT TO LOWER RIGHT FILL U+25A7

BlockGeometric Shapes
CategoryOther Symbol
UTF-80xE2 0x96 0xA7
UTF-160xFF 0xFE 0xA7 0x25
UTF-320xFF 0xFE 0x0 0x0 0xA7 0x25 0x0 0x0
HTML▧
Pythonu"\u25A7"