Remove unneeded code

Also a small formatting change

Author: jkugler

cyclonedx/model/__init__.py

@@ -51,6 +51,7 @@
     SchemaVersion1Dot6,
 )
 
+
 @serializable.serializable_enum
 class DataFlow(str, Enum):
     """
@@ -1197,6 +1198,7 @@ def __repr__(self) -> str:
 
 # Importing here to avoid a circular import
 from .tool import Tool  # pylint: disable=wrong-import-position
+
 ThisTool = Tool(
     vendor='CycloneDX',
     name='cyclonedx-python-lib',
@@ -1234,4 +1236,5 @@ def __repr__(self) -> str:
             type=ExternalReferenceType.WEBSITE,
             url=XsUri('https://github.com/CycloneDX/cyclonedx-python-lib/#readme')
         )
-    ])
+    ]
+)

cyclonedx/model/bom.py

@@ -137,17 +137,6 @@ def tools(self, tools: Union[Iterable[Tool], ToolsRepository]) -> None:
         if isinstance(tools, ToolsRepository):
             self._tools = tools
         else:
-            # This allows the old behavior of assigning the list of tools directly to bom.metadata.tools
-            warn(
-                '`bom.metadata.tools` as a list of Tool objects is deprecated from CycloneDX v1.5 '
-                'onwards. Please use lists of `Component` and `Service` objects as `tools.components` '
-                'and `tools.services`, respectively.'
-            )
-            if hasattr(self, '_tools') and (self._tools._components or self._tools._services):  # pylint: disable=protected-access
-                raise MutuallyExclusivePropertiesException(
-                    'Cannot serialize both old (CycloneDX <= 1.4) and new '
-                    '(CycloneDX >= 1.5) format for tools.'
-                )
             self._tools = ToolsRepository(tools=tools)
 
     @property