removes duplicate eval
provides error prompt for cases where users reassign the variable in data structure assignment questions
refactors data structure access eval
makes colorized error print method dynamic for NoMethodError and true NameErrors
clarifies language related to syntax errors
adds additional question data for data structure assignment
adds data to data_structure_assignment questions
removes unnecessary use of 'self' from data structure access questions. also refactors rescues of NameError and NoMethodError into single handler