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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 find_template(repo_dir):
 """Determine which child directory of `repo_dir` is the project template. :param repo_dir: Local directory of newly cloned repo. :returns project_template: Relative path to project template. """

    logger.debug('Searching {} for the project template.'.format(repo_dir))

    repo_dir_contents = os.listdir(repo_dir)

    project_template = None
    for item in repo_dir_contents:
        if 'cookiecutter' in item and '{{' in item and '}}' in item:
            project_template = item
            break

    if project_template:
        project_template = os.path.join(repo_dir, project_template)
        logger.debug(
            'The project template appears to be {}'.format(project_template)
        )
        return project_template
    else:
        raise NonTemplatedInputDirException