Bug.  Doctests Readme line 405

### PyShp Version

3.2.2

### Python Version

Iron 2.7

### Your code

```shell
ipy shapefile.py
```

### Full stacktrace

```shell
File "README.md", line 405, in README
Failed example:
    sf.bbox
Expected:
    [-122.515048, 37.652916, -122.327622, 37.863433]
Got:
    [-122.51504799999999, 37.652915999999998, -122.32762200000001, 37.863433000000001]
```

### Other notes

_No response_