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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 validate_uses_tls_for_keystone(audit_options):
 """Verify that TLS is used to communicate with Keystone."""

    section = _config_section(audit_options, 'keystone_authtoken')
    assert section is not None, "Missing section 'keystone_authtoken'"
    assert not section.get('insecure') and \
        "https://" in section.get("auth_uri"), \
        "TLS is not used for Keystone"