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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 validate_fillna_kwargs(value, method, validate_scalar_dict_value=True):
 """Validate the keyword arguments to 'fillna'. This checks that exactly one of 'value' and 'method' is specified. If 'method' is specified, this validates that it's a valid method. Parameters value, method : object The 'value' and 'method' keyword arguments for 'fillna'. validate_scalar_dict_value : bool, default True Whether to validate that 'value' is a scalar or dict. Specifically, validate that it is not a list or tuple. Returns ------- value, method : object """

    from pandas.core.missing import clean_fill_method

    if value is None and method is None:
        raise ValueError("Must specify a fill 'value' or 'method'.")
    elif value is None and method is not None:
        method = clean_fill_method(method)

    elif value is not None and method is None:
        if validate_scalar_dict_value and isinstance(value, (list, tuple)):
            raise TypeError('"value" parameter must be a scalar or dict, but '
                            'you passed a "{0}"'.format(type(value).__name__))

    elif value is not None and method is not None:
        raise ValueError("Cannot specify both 'value' and 'method'.")

    return value, method