AttributeError: 'Unparser' object has no attribute '_str'. Did you mean: '_Str'? pyflowchart 0.3.1 with python 3.11 and astunparse 1.6.3

[cdfmlr]

As pyflowchart 0.3.1 used with python 3.11 and astunparse 1.6.3 throws an exception:

Traceback (most recent call last):
  File "C:\Downloads\sc-navigator-model-generation-cp\APO Input Workflow\src\flowchart.py", line 12, in <module>
    fc = pfc.parse(code)
         ^^^^^^^^^^^^^^^
  File "C:\Downloads\sc-navigator-model-generation-cp\APO Input Workflow\src\new_env\Lib\site-packages\pyflowchart\ast_node.py", line 659, in parse
    node = ast_node_class(ast_object, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Downloads\sc-navigator-model-generation-cp\APO Input Workflow\src\new_env\Lib\site-packages\pyflowchart\ast_node.py", line 463, in __init__
    OperationNode.__init__(self, operation=self.ast_to_source())
                                           ^^^^^^^^^^^^^^^^^^^^
  File "C:\Downloads\sc-navigator-model-generation-cp\APO Input Workflow\src\new_env\Lib\site-packages\pyflowchart\ast_node.py", line 33, in ast_to_source
    return astunparse.unparse(self.ast_object).strip()
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Downloads\sc-navigator-model-generation-cp\APO Input Workflow\src\new_env\Lib\site-packages\astunparse\__init__.py", line 13, in unparse
    Unparser(tree, file=v)
  File "C:\Downloads\sc-navigator-model-generation-cp\APO Input Workflow\src\new_env\Lib\site-packages\astunparse\unparser.py", line 38, in __init__
    self.dispatch(tree)
  File "C:\Downloads\sc-navigator-model-generation-cp\APO Input Workflow\src\new_env\Lib\site-packages\astunparse\unparser.py", line 65, in dispatch
    meth = getattr(self, "_"+tree.__class__.__name__)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'Unparser' object has no attribute '_str'. Did you mean: '_Str'?

How do I resolve this issue?

Originally posted by @kaasima10 in #28 (comment)

[cdfmlr]

@kaasima10 I have tested pyflowchart 0.3.1 with python 3.11 and astunparse 1.6.3 as you described, on some basic cases I tried, it works fine. Would you mind to post your inputted python source code and command executed that helps reproduce this problem?

[kaasima10]

this is my python code :-

import pyflowchart as pfc
import inspect

def example_function(x):
if x > 0:
return 'Positive'
elif x < 0:
return 'Negative'
else:
return 'Zero'

code = inspect.getsource(example_function)
fc = pfc.parse(code)
flowchart = fc.flowchart()
print(flowchart)

@cdfmlr I encountered an AttributeError when attempting to convert a simple Python function to a flowchart using the pyflowchart library. The function is straightforward, but the error occurs during the conversion process.

[cdfmlr]

Thanks. Have figured it out.

You should use:

from pyflowchart import Flowchart

...

fc = Flowchart.from_code(code)

...

instead of:

import pyflowchart as pfc

...

fc = pfc.parse(code)

...

As described in our document section Python to Flowchart, Flowchart.from_code is the right method you are expected to converts python source code from a str to the flowchart:

pyflowchart/pyflowchart/flowchart.py

Lines 42 to 56 in dcb5128

	@staticmethod
	def from_code(code: str, field: str = "", inner=True, simplify=True, conds_align=False):
	"""
	Get a Flowchart instance from a str of Python code.
	Args:
	code: str, Python code to draw flowchart
	field: str, path to field (function) you want to draw flowchart
	inner: bool, True: parse the body of field; Field: parse the body as an object
	simplify: bool, for If & Loop statements: simplify the one-line-body or not.
	conds_align: bool, for consecutive If statements: conditionNode alignment support (Issue#14) or not
	Returns:
	A Flowchart instance parsed from given code.

Meanwhile, parse is an internal function that parses the abstract syntax trees of python codes, instead of a str of python source code:

pyflowchart/pyflowchart/ast_node.py

Lines 929 to 943 in dcb5128

	def parse(ast_list: List[_ast.AST], **kwargs) -> ParseProcessGraph:
	"""
	parse an ast_list (from _ast.Module/FunctionDef/For/If/etc.body)
	Args:
	ast_list: a list of _ast.AST object
	Keyword Args:
	* simplify: for If & Loop: simplify the one line body cases
	* conds_align: for If: allow the align-next option set for the condition nodes.
	See https://github.com/cdfmlr/pyflowchart/issues/14
	Returns:
	ParseGraph
	"""

Users shall never call this function from the out of the package.