add message and install guide for required package "py3dbp"
# License: MIT License
from typing import Iterable, List
import math
+import sys
+
import ezdxf
from ezdxf.entities import DXFGraphic
from ezdxf.math import Matrix44, BoundingBox
from ezdxf.path import Path, make_path, nesting
+try:
import py3dbp
+except ImportError:
+ print(
+ 'This example requires the package "py3dbp", a pure Python package'
+ " hosted on PyPI.\nInstall using pip:\n\n pip install py3dbp\n"
+ )
+ sys.exit(1)
from py3dbp.constants import RotationType
UNLIMITED = 1_000_000
