ALGHeArT/sympy — comment on commit 44410640d3d26c7d56c98e06e8db72cd83d21378
File:  line 0
By smichr:

You have to put the rhs in quotes:

'Matrix([[1, 2], [3, 4]])'

Also, indent the line to the 4th column. Then submit this as a new pull request.