PyFile:shellAssignment2.py
  PyAssignmentStatement
    PyTargetExpression: my_files_1
      PsiElement(Py:IDENTIFIER)('my_files_1')
    PsiWhiteSpace(' ')
    PsiElement(Py:EQ)('=')
    PsiWhiteSpace(' ')
    PyEmptyExpression
      PsiElement(Py:SHELL_COMMAND)('!ls -la')