CCPN import errors and pythonpath

Once CCPN is installed, the user can nevertheless get errors concerning the import of CCPN. Typical errors are encountered:

when checking the ARIA installation (command 'aria2 ./check.py')

CCPN distribution:

Could not import the following modules: ccpnmr, ccpnmr.format, ccpnmr.analysis
This does not matter, as long as you do not intend to use the CCPBN data model. 
Otherwise, please make sure that the environment variable
CCPNMR_TOP_DIR is set correctly.

when trying to convert the input data files into an ARIA project (command 'aria2 --convert -t convert.xml ')

from ccp.general.Io import getChemCompHead
> ImportError: No module named ccp.general.Io

Solution: You have to modify your environment file (.cshrc or .bashrc), by including the line:

setenv PYTHONPATH .:$CCPNMR_TOP_DIR/ccpnmr1.0/python

in your .cshrc file, or the line:

export PYTHONPATH=$PYTHONPATH:$CCPNMR_TOP_DIR/ccpnmr1.0/python