INSERTing rows from external file

I have a file with 5500 rows formated as 'INSERT INTO <table>
(column_names) VALUES <values>;' that I thought I could read using psql from
the command line. However, the syntax, 'psql <database_name> < filename.sql'
throws an error at the beginning of the first INSERT statement.

In the INSERT manual page I see no example or other insight on adding a
large number of rows to a table from an external .sql file. Please point me
to the reference on how to do this.

Rich