This uses ezdxf load dxf files, connect individal LINE segments into POLYLINE, and correct their direction based on nesting level (assuming that it represents a 2d shape).
Requirements:
- Python 2.7 or 3+
ezdxf
dxf_fix in.dxf [ -o out.dxf ] will write out.dxf if provided, otherwise in.dxf.new