abaqus python script

[nimaet]

Hi,
I Have written a script to make a sequence of elements from an existing model data base. when I run the script from (File/run script)
abaqus shows an error:
AccessError : mdb no longer exists
but when I run the same code in "Kernel Command Line Interface" abaqus does not show any error
here is my code
mdb1 = openMdb(pathName = 'test1.cae')
mdb2 = openMdb(pathName = 'test1.cae')
element_set_mdb1 = mdb1.models['Model-1'].parts['Part-1'].elements.sequenceFromLabels(labels=element_labels_mdb1)
Can abaqus open two MDBs simultaneously?
does anyone have any idea?