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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 default_styles():
 """Generate default ODF styles."""


    styles = {}

    def _add_style(name, **kwargs):
        styles[name] = _create_style(name, **kwargs)

    _add_style('heading-1',
               family='paragraph',
               fontsize='24pt',
               fontweight='bold',
               )
    _add_style('heading-2',
               family='paragraph',
               fontsize='22pt',
               fontweight='bold',
               )
    _add_style('heading-3',
               family='paragraph',
               fontsize='20pt',
               fontweight='bold',
               )
    _add_style('heading-4',
               family='paragraph',
               fontsize='18pt',
               fontweight='bold',
               )
    _add_style('heading-5',
               family='paragraph',
               fontsize='16pt',
               fontweight='bold',
               )
    _add_style('heading-6',
               family='paragraph',
               fontsize='14pt',
               fontweight='bold',
               )
    _add_style('normal-paragraph',
               family='paragraph',
               fontsize='12pt',
               marginbottom='0.25cm',
               )
    _add_style('code',
               family='paragraph',
               fontsize='10pt',
               fontweight='bold',
               fontfamily='Courier New',
               color='#555555',
               )
    _add_style('quote',
               family='paragraph',
               fontsize='12pt',
               fontstyle='italic',
               )
    _add_style('list-paragraph',
               family='paragraph',
               fontsize='12pt',
               marginbottom='.1cm',
               )
    _add_style('sublist-paragraph',
               family='paragraph',
               fontsize='12pt',
               marginbottom='.1cm',
               )
    _add_style('numbered-list-paragraph',
               family='paragraph',
               fontsize='12pt',
               marginbottom='.1cm',
               )

    _add_style('normal-text',
               family='text',
               fontsize='12pt',
               )
    _add_style('italic',
               family='text',
               fontstyle='italic',
               fontsize='12pt',
               )
    _add_style('bold',
               family='text',
               fontweight='bold',
               fontsize='12pt',
               )
    _add_style('url',
               family='text',
               fontsize='12pt',
               fontweight='bold',
               fontfamily='Courier',
               )
    _add_style('inline-code',
               family='text',
               fontsize='10pt',
               fontweight='bold',
               fontfamily='Courier New',
               color='#555555',
               )

    styles['_numbered_list'] = _numbered_style()

    return styles