COPY FROM - force a value

Is there a way to force a value when you're doing a COPY FROM, importing
a file into a table?

Here's my query as it is now:

COPY filetable (value1, value2, value3, value4, forcevalue1,
forcevalue2)
FROM 'C:\\InsertFiles\\thisfile.txt'
WITH DELIMITER AS ' '
;

The file only contains data for values 1 through 4. I'd like to insert
values for the last two fields. This is what I had in mind, which
doesn't work:

COPY filetable (value1, value2, value3, value4, forcevalue1,
forcevalue2)
FROM 'C:\\InsertFiles\\thisfile.txt'
WITH DELIMITER AS ' ',
forcevalue1 = 1,
forcevalue2 = 'this value'
;

TIA

-Jeff
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