师傅不见了

Support MathType and oMathML read and write

2

## Description # MathType ... # oMathML ... ## Expected Behavior ## Actual Behavior Please include a reproducible code snippet or document attachment that demonstrates the issue.

优化文件读取，减少内存使用，提升性能

1

只更改了city类，District类和BaseStation类由于没有库文件，没有修改。

can not parse latex content

7

in `instantiate_choice': selection '102' does not exist in :choices for obj.equation[0].payload (IndexError)