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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 describe_keypairs(self, *keypair_names):
 """Returns information about key pairs available."""

        keypairs = {}
        for index, keypair_name in enumerate(keypair_names):
            keypairs["KeyName.%d" % (index + 1)] = keypair_name
        query = self.query_factory(
            action="DescribeKeyPairs", creds=self.creds,
            endpoint=self.endpoint, other_params=keypairs)
        d = query.submit()
        return d.addCallback(self.parser.describe_keypairs)