Remove useless imports

midisnake/structure.py

@@ -19,7 +19,7 @@
 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
-from typing import AnyStr, List, Dict, Any, cast
+from typing import List
 from io import BufferedReader
 from abc import ABCMeta, abstractmethod