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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 copy_on_s3(self, src_file_name, dst_file_name, bucket_name):
 """ Copies src file to destination within a bucket. """

        try:
            self.s3_client.head_bucket(Bucket=bucket_name)
        except botocore.exceptions.ClientError as e:  # pragma: no cover
            # If a client error is thrown, then check that it was a 404 error.
            # If it was a 404 error, then the bucket does not exist.
            error_code = int(e.response['Error']['Code'])
            if error_code == 404:
                return False

        copy_src = {
            "Bucket": bucket_name,
            "Key": src_file_name
        }
        try:
            self.s3_client.copy(
                CopySource=copy_src,
                Bucket=bucket_name,
                Key=dst_file_name
            )
            return True
        except botocore.exceptions.ClientError:  # pragma: no cover
            return False