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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 dump_value(key, value, f, indent=0):
    '''Save a value of any libconfig type

    This function serializes takes ``key`` and ``value`` and serializes them
    into ``f``. If ``key`` is ``None``, a list-style output is produced.
    Otherwise, output has ``key = value`` format.
    '''

    spaces = ' ' * indent

    if key is None:
        key_prefix = ''
        key_prefix_nl = ''
    else:
        key_prefix = key + ' = '
        key_prefix_nl = key + ' =\n' + spaces

    dtype = get_dump_type(value)
    if dtype == 'd':
        f.write(u'{}{}{{\n'.format(spaces, key_prefix_nl))
        dump_dict(value, f, indent + 4)
        f.write(u'{}}}'.format(spaces))
    elif dtype == 'l':
        f.write(u'{}{}(\n'.format(spaces, key_prefix_nl))
        dump_collection(value, f, indent + 4)
        f.write(u'\n{})'.format(spaces))
    elif dtype == 'a':
        f.write(u'{}{}[\n'.format(spaces, key_prefix_nl))
        value_dtype = get_array_value_dtype(value)

        # If int array contains one or more Int64, promote all values to i64.
        if value_dtype == 'i64':
            value = [LibconfInt64(v) for v in value]
        dump_collection(value, f, indent + 4)
        f.write(u'\n{}]'.format(spaces))
    elif dtype == 's':
        f.write(u'{}{}{}'.format(spaces, key_prefix, dump_string(value)))
    elif dtype == 'i' or dtype == 'i64':
        f.write(u'{}{}{}'.format(spaces, key_prefix, dump_int(value)))
    elif dtype == 'f' or dtype == 'b':
        f.write(u'{}{}{}'.format(spaces, key_prefix, value))
    else:
        raise ConfigSerializeError("Can not serialize object %r of type %s" %
                                   (value, type(value)))