from typing import Dict


def get_input_data(input_section: Dict) -> str:
    """Gets playbook single input item - support simple and complex input.

    Args:
        input_section (dict): playbook input item.

    Returns:
        (str): The playbook input item's value.
    """
    default_value = input_section.get('value')
    if isinstance(default_value, str):
        return default_value

    if default_value:
        complex_field = default_value.get('complex')
        if complex_field:
            return f"{complex_field.get('root')}.{complex_field.get('accessor')}"
        return default_value.get('simple')

    return ''