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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 Font(name=None, source="sys", italic=False, bold=False, size=20):
 """Unifies loading of fonts. :param name: name of system-font or filepath, if None is passed the default system-font is loaded :type name: str :param source: "sys" for system font, or "file" to load a file :type source: str """

    assert source in ["sys", "file"]
    if not name:
        return pygame.font.SysFont(pygame.font.get_default_font(), 
        size, bold=bold, italic=italic)
    if source == "sys":
        return pygame.font.SysFont(name, 
        size, bold=bold, italic=italic)
    else:
        f = pygame.font.Font(name, size)
        f.set_italic(italic)
        f.set_bold(bold)
        return f