restype_order_with_x
====================

氨基酸种类列表使用单字符表示下对应序号，顺序与 `restypes_with_x` 列表内氨基酸顺序一致，数据类型是字典，字典键值为氨基酸单字符表示，值为序号。

+-----+-------+
| key | value |
+=====+=======+
| A   | 0     |
+-----+-------+
| R   | 1     |
+-----+-------+
| N   | 2     |
+-----+-------+
| D   | 3     |
+-----+-------+
| C   | 4     |
+-----+-------+
| Q   | 5     |
+-----+-------+
| E   | 6     |
+-----+-------+
| G   | 7     |
+-----+-------+
| H   | 8     |
+-----+-------+
| I   | 9     |
+-----+-------+
| L   | 10    |
+-----+-------+
| K   | 11    |
+-----+-------+
| M   | 12    |
+-----+-------+
| F   | 13    |
+-----+-------+
| P   | 14    |
+-----+-------+
| S   | 15    |
+-----+-------+
| T   | 16    |
+-----+-------+
| W   | 17    |
+-----+-------+
| Y   | 18    |
+-----+-------+
| V   | 19    |
+-----+-------+
| X   | 20    |
+-----+-------+