target_scanner issue

stacktrace

In Tool example _example_scanner(src/file1.exin, env, ()) [Environment:first one]
scons: *** [src/file1.example] TypeError : _example_target_scanner() takes exactly 1 argument (3 given)
scons: internal stack trace:
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Job.py", line 199, in start
    task.prepare()
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Script/Main.py", line 176, in prepare
    return SCons.Taskmaster.OutOfDateTask.prepare(self)
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Taskmaster.py", line 179, in prepare
    self.exception_raise()
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Taskmaster.py", line 559, in _exception_raise
    exec("raise exc_type, exc_value, exc_traceback")
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Taskmaster.py", line 837, in _find_next_ready_node
    children = executor.get_all_children()
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Executor.py", line 323, in get_all_children
    result.extend(target.children())
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Node/__init__.py", line 1370, in children
    self.scan()
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Node/__init__.py", line 1068, in scan
    executor.scan_targets(scanner)
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Executor.py", line 483, in scan_targets
    self.scan(scanner, self.get_all_targets())
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Executor.py", line 505, in scan
    deps.extend(node.get_implicit_deps(env, scanner, path, kw))
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Node/__init__.py", line 957, in get_implicit_deps
    included_deps = [x for x in node.get_found_includes(env, scanner, path) if x not in seen]
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Node/FS.py", line 2891, in get_found_includes
    result = [n.disambiguate() for n in scanner(self, env, path)]
  File "/Users/bdbaddog/devel/scons/git/as_scons/src/script/../engine/SCons/Scanner/__init__.py", line 213, in __call__
    node_list = self.function(node, env, path)
scons: building terminated because of errors.