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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 tab(tab_name, element_list=None, section_list=None):
 """ Returns a dictionary representing a new tab to display elements. This can be thought of as a simple container for displaying multiple types of information. Args: tab_name: The title to display element_list: The list of elements to display. If a single element is given it will be wrapped in a list. section_list: A list of sections to display. Returns: A dictionary with metadata specifying that it is to be rendered as a page containing multiple elements and/or tab. """

    _tab = {
            'Type': 'Tab',
            'Title': tab_name,
            }

    if element_list is not None:
        if isinstance(element_list, list):
            _tab['Elements'] = element_list
        else:
            _tab['Elements'] = [element_list]
    if section_list is not None:
        if isinstance(section_list, list):
            _tab['Sections'] = section_list
        else:
            if 'Elements' not in section_list:
                _tab['Elements'] = element_list
            else:
                _tab['Elements'].append(element_list)
    return _tab