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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def verify_cot_signatures(chain):
 """Verify the signatures of the chain of trust artifacts populated in ``download_cot``. Populate each link.cot with the chain of trust json body. Args: chain (ChainOfTrust):
 the chain of trust to add to. Raises: CoTError: on failure. """

    for link in chain.links:
        unsigned_path = link.get_artifact_full_path('public/chain-of-trust.json')
        ed25519_signature_path = link.get_artifact_full_path('public/chain-of-trust.json.sig')
        verify_link_ed25519_cot_signature(chain, link, unsigned_path, ed25519_signature_path)