def _repository_exists(client, repo_name):
    """
    Checks if a repository exists
    :param client: boto3.client The ECR client 
    :param repo_name: str The name of the repository to check
    """
    response = client.describe_repositories()
    # will either return a list of dicts or empty dict
    for repository in response.get('repositories', {}):
        # if empty dict is returned, loop skipped and False returned
        if repository.get('repositoryName') == repo_name:
            return True
    return False