I wanted to use DC to conduct synthesis but an error occurred.
I have done the actions below:

1. Add the dc plugin from the hammer-synopsys-plugins to the direction: hammer/synthesis(installed by pip);
2. Add class (SynopsysTool) to the file: hammer/vlsi/hammer-vlsi-impl.py.(installed by pip)

And the error showed:

File "/home/rfic/chipyard/.conda-env/lib/python3.10/site-packages/hammer/vlsi/hammer_vlsi_impl.py", line 2377, in load_tool
    tool: HammerTool = tool_class()
TypeError: Can't instantiate abstract class DC with abstract methods post_synth_sdc, version_number

How can I solve this problem?