def srcdir_find_file(self, filename):
        try:
            memo_dict = self._memo['srcdir_find_file']
        except KeyError:
            memo_dict = {}
            self._memo['srcdir_find_file'] = memo_dict
        else:
            try:
                return memo_dict[filename]
            except KeyError:
                pass

        def func(node):
            if (isinstance(node, File) or isinstance(node, Entry)) and \
               (node.is_derived() or node.exists()):
                    return node
            return None

        norm_name = _my_normcase(filename)

        for rdir in self.get_all_rdirs():
            try: node = rdir.entries[norm_name]
            except KeyError: node = rdir.file_on_disk(filename)
            else: node = func(node)
            if node:
                result = (node, self)
                memo_dict[filename] = result
                return result

        for srcdir in self.srcdir_list():
            for rdir in srcdir.get_all_rdirs():
                try: node = rdir.entries[norm_name]
                except __HOLE__: node = rdir.file_on_disk(filename)
                else: node = func(node)
                if node:
                    result = (File(filename, self, self.fs), srcdir)
                    memo_dict[filename] = result
                    return result

        result = (None, None)
        memo_dict[filename] = result
        return result
dataset/ETHPy150Open kayhayen/Nuitka/nuitka/build/inline_copy/lib/scons-2.3.2/SCons/Node/FS.py/Dir.srcdir_find_file