Inline math problem

Hello,
Whenever I try to inline math in a mdpp file, markdown-pp returns a weird output. For example, for the input:
$2^n$

The output is:
```
![2^n](<html>
<head><title>405 Not Allowed</title></head>
<body bgcolor="white">
<center><h1>405 Not Allowed</h1></center>
</body>
</html> "2^n")
```

I have tested this both on Python 2.7.15 and 3.6.8.