I am new to chimera.  I have been building and modifying several structures using command-line, and have been successful except for setting a specific torsion to a specified angle.  The torsion is not phi, psi, etc.  I thought I could define the torsion as a specific attribute using an attribute assignment file and defattr.  In my model, the torsion is ":1.A@O3 :1.A@S1 :1.B@O2 :1.B@S2", and I would like to set it to a value of 15.  So, my assignment file would be (?):

attribute: MyTors

match mode: any

recipient: atoms

            :1.A@O3 :1.A@S1 :1.B@O2 :1.B@S2 15

Then from command-line I would use: defattr MyTors

Is this correct?

Thank you for the help,

Jerry