How do I manipulate a variable whose name conflicts with PDB commands?

Use an exclamation mark ! before a statement to have it run :

python -m pdb test.py
> /home/user/test.py(1)<module>()
-> print('foo')
(Pdb) !n = 77
(Pdb) !n
77
(Pdb) n
foo
> /home/user/test.py(2)<module>()
-> print('bar')
(Pdb)

The docs say:

! statement

Execute the (one-line) statement in the context of the current stack frame. The exclamation point can be omitted unless the first word of the statement resembles a debugger command. [...]

You can use semicolons, so just put something else in front of it:

ipdb> print n
2
ipdb> n
> 145 <some code here>
  146
  147

ipdb> 1; n=4
1
ipdb> print n
4

That is not the direct answer to your question, but it may help you: PuDB is a console-based visual interface for PDB which separates commands from variable manipulation by design.