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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 abspath_to_urlpath(path, base, os_sep=os.sep):
    '''
    Make filesystem absolute path uri relative using given absolute base path.

    :param path: absolute path
    :param base: absolute base path
    :param os_sep: path component separator, defaults to current OS separator
    :return: relative uri
    :rtype: str or unicode
    :raises OutsideDirectoryBase: if resulting path is not below base
    '''
    return relativize_path(path, base, os_sep).replace(os_sep, '/')