fix: resolve N817 lint error by using explicit imports from defusedxml

Replace 'import defusedxml.ElementTree as ET' with explicit imports
(fromstring, ParseError, Element) to satisfy ruff N817 rule that flags
CamelCase imported as acronym.

Co-Authored-By: João <joao@crewai.com>

lib/crewai-tools/src/crewai_tools/tools/arxiv_paper_tool/arxiv_paper_tool.py

@@ -6,9 +6,10 @@ from typing import ClassVar
 import urllib.error
 import urllib.parse
 import urllib.request
+from xml.etree.ElementTree import Element
 
 from crewai.tools import BaseTool, EnvVar
-import defusedxml.ElementTree as ET
+from defusedxml.ElementTree import fromstring
 from pydantic import BaseModel, ConfigDict, Field
 
 
@@ -90,7 +91,7 @@ class ArxivPaperTool(BaseTool):
             logger.error(f"Error fetching data from Arxiv: {e}")
             raise
 
-        root = ET.fromstring(data)
+        root = fromstring(data)
         papers = []
 
         for entry in root.findall(self.ATOM_NAMESPACE + "entry"):
@@ -121,11 +122,11 @@ class ArxivPaperTool(BaseTool):
         return papers
 
     @staticmethod
-    def _get_element_text(entry: ET.Element, element_name: str) -> str | None:
+    def _get_element_text(entry: Element, element_name: str) -> str | None:
         elem = entry.find(f"{ArxivPaperTool.ATOM_NAMESPACE}{element_name}")
         return elem.text.strip() if elem is not None and elem.text else None
 
-    def _extract_pdf_url(self, entry: ET.Element) -> str | None:
+    def _extract_pdf_url(self, entry: Element) -> str | None:
         for link in entry.findall(self.ATOM_NAMESPACE + "link"):
             if link.attrib.get("title", "").lower() == "pdf":
                 return link.attrib.get("href")

lib/crewai-tools/tests/rag/test_xml_loader.py

@@ -196,5 +196,4 @@ class TestXMLLoader:
         """Verify that ArxivPaperTool imports from defusedxml, not xml.etree.ElementTree."""
         import crewai_tools.tools.arxiv_paper_tool.arxiv_paper_tool as arxiv_module
 
-        ET = arxiv_module.ET
-        assert "defusedxml" in ET.__name__
+        assert "defusedxml" in arxiv_module.fromstring.__module__

lib/crewai-tools/tests/tools/arxiv_paper_tool_test.py

@@ -1,7 +1,7 @@
 from pathlib import Path
 from unittest.mock import MagicMock, patch
 import urllib.error
-import defusedxml.ElementTree as ET
+from defusedxml.ElementTree import ParseError
 
 from crewai_tools import ArxivPaperTool
 import pytest
@@ -108,7 +108,7 @@ def test_invalid_xml_response(mock_urlopen, tool):
     mock_response.status = 200
     mock_urlopen.return_value.__enter__.return_value = mock_response
 
-    with pytest.raises(ET.ParseError):
+    with pytest.raises(ParseError):
         tool.fetch_arxiv_data("quantum", 1)