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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 _load_templates(workflow: dict, templates_root: str):
 """Load templates keys."""

    workflow_template_path = join(templates_root, workflow['id'],
                                  workflow['version'])
    for i, stage_config in enumerate(workflow['stages']):
        stage_template_path = join(workflow_template_path,
                                   stage_config['id'],
                                   stage_config['version'])
        for config_type in ['ee_config', 'app_config']:
            for key, value in stage_config[config_type].items():
                if 'template' in key:
                    template_file = join(stage_template_path, value)
                    with open(template_file, 'r') as file:
                        template_str = file.read()
                        workflow['stages'][i][config_type][key] = template_str