 <OpenGeoSysProjectDiff base_file="../1d_decay_chain_GIA.prj">

   <add sel="/*">

     <python_script>python_error_Dirichlet.py</python_script>

   </add>

   <add sel="//process_variable[name='pressure']/boundary_conditions">

     <boundary_condition>

       <type>Python</type>

       <bc_object>bc</bc_object>

       <mesh>1d_decay_chain_upstream</mesh>

     </boundary_condition>

   </add>

 </OpenGeoSysProjectDiff>