luaparser.utils.visitor.VisitorException: No visitor found for class <enum 'StringDelimiter'>

[RandyChihuahua]

Using the basic command:

from luaparser import ast

src = """
local function sayHello()
print('hello world !')
end
sayHello()
"""

tree = ast.parse(src)
print(ast.to_pretty_str(tree))

I get this:
print(ast.to_pretty_str(tree))
File "~Python37\lib\site-packages\luaparser\ast.py", line 38, in to_pretty_str
return printers.PythonStyleVisitor(indent).visit(root)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 37, in _visitor_impl
return method(self, arg)
File "~Python37\lib\site-packages\luaparser\printers.py", line 107, in visit
res += self.visit(attrValue)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 37, in _visitor_impl
return method(self, arg)
File "~Python37\lib\site-packages\luaparser\printers.py", line 107, in visit
res += self.visit(attrValue)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 29, in _visitor_impl
return method(self, arg)
File "~Python37\lib\site-packages\luaparser\printers.py", line 80, in visit
res += self.indent_str(False) + self.visit(itemValue)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 37, in _visitor_impl
return method(self, arg)
File "~Python37\lib\site-packages\luaparser\printers.py", line 107, in visit
res += self.visit(attrValue)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 37, in _visitor_impl
return method(self, arg)
File "~Python37\lib\site-packages\luaparser\printers.py", line 107, in visit
res += self.visit(attrValue)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 29, in _visitor_impl
return method(self, arg)
File "~Python37\lib\site-packages\luaparser\printers.py", line 80, in visit
res += self.indent_str(False) + self.visit(itemValue)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 37, in _visitor_impl
return method(self, arg)
File "~Python37\lib\site-packages\luaparser\printers.py", line 107, in visit
res += self.visit(attrValue)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 29, in _visitor_impl
return method(self, arg)
File "~Python37\lib\site-packages\luaparser\printers.py", line 80, in visit
res += self.indent_str(False) + self.visit(itemValue)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 37, in _visitor_impl
return method(self, arg)
File "~Python37\lib\site-packages\luaparser\printers.py", line 111, in visit
res += self.indent_str() + attr + ': ' + self.visit(attrValue)
File "~Python37\lib\site-packages\luaparser\utils\visitor.py", line 40, in _visitor_impl
raise VisitorException('No visitor found for class ' + str(type(arg)))
luaparser.utils.visitor.VisitorException: No visitor found for class <enum 'StringDelimiter'>

I am using python 3.7.9 and vs code.
Note that ~ is used to remove references to my local machine.