human
I am working on the file "Notebooks/Using nbconvert as a Library.ipynb".
The first task is:
Example
The following demonstration was requested in an IPython GitHub issue, the ability to exclude a cell by index. 
Inject cells is similar, and won't be covered here.  If you want to inject static content at the beginning/end of a notebook, use a custom template.
Can you write Python program for it?

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Write me a the Python program you requested?
assistant
#Here is the Python program you requested.

from traitlets import Integer

class PelicanSubCell(Preprocessor):
    """A Pelican specific preprocessor to remove some of the cells of a notebook"""
    
    # I could also read the cells from nbc.metadata.pelican is someone wrote a JS extension
    # But I'll stay with configurable value. 
    start = Integer(0, config=True, help="first cell of notebook to be converted")
    end   = Integer(-1, config=True, help="last cell of notebook to be converted")
    
    def preprocess(self, nb, resources):

        #nbc = deepcopy(nb)
        nbc = nb
        # don't print in real preprocessor !!!
        print("I'll keep only cells from ", self.start, "to ", self.end, "\n\n")
        nbc.cells = nb.cells[self.start:self.end]                    
        return nbc, resources

# I create this on the fly, but this could be loaded from a DB, and config object support merging...
c =  Config()
c.PelicanSubCell.enabled = True
c.PelicanSubCell.start = 4
c.PelicanSubCell.end = 6