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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 _head_object(s3_conn, bucket, key):
 """Retrieve information about an object in S3 if it exists. Args: s3_conn (botocore.client.S3):
 S3 connection to use for operations. bucket (str):
 name of the bucket containing the key. key (str):
 name of the key to lookup. Returns: dict: S3 object information, or None if the object does not exist. See the AWS documentation for explanation of the contents. Raises: botocore.exceptions.ClientError: any error from boto3 other than key not found is passed through. """

    try:
        return s3_conn.head_object(Bucket=bucket, Key=key)
    except botocore.exceptions.ClientError as e:
        if e.response['Error']['Code'] == '404':
            return None
        else:
            raise