a) You must cause the modified files to carry prominent notices
stating that you changed the files and the date of any change.
b) You must cause any work that you distribute or publish, that in
whole or in part contains or is derived from the Program or any
part thereof, to be licensed as a whole at no charge to all third
parties under the terms of this License.
c) If the modified program normally reads commands
interactively when run, you must cause it, when started running
for such interactive use in the most ordinary way, to print or
display an announcement including an appropriate copyright
notice and a notice that there is no warranty (or else, saying
that you provide a warranty) and that users may redistribute
the program under these conditions, and telling the user how
to view a copy of this License. (Exception: if the Program itself is
interactive but does not normally print such an announcement,
your work based on the Program is not required to print an
announcement.)
These requirements apply to the modified work as a whole.
If identifiable sections of that work are not derived from the
Program, and can be reasonably considered independent and
separate works in themselves, then this License, and its terms,
do not apply to those sections when you distribute them as
separate works. But when you distribute the same sections
as part of a whole which is a work based on the Program, the
distribution of the whole must be on the terms of this License,
whose permissions for other licensees extend to the entire
whole, and thus to each and every part regardless of who wrote
it.
Thus, it is not the intent of this section to claim rights or contest
your rights to work written entirely by you; rather, the intent is
to exercise the right to control the distribution of derivative or
collective works based on the Program.
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