Test pickle protocol 4 in test_pickling.py
Test pickle protocol 4 in test_pickling.py

kaushik94/sympy,skidzo/sympy,yashsharan/sympy,jaimahajan1997/sympy,kaushik94/sympy,chaffra/sympy,kaushik94/sympy,madan96/sympy,chaffra/sympy,yashsharan/sympy,madan96/sympy,skidzo/sympy,yashsharan/sympy,chaffra/sympy,jaimahajan1997/sympy,madan96/sympy,jaimahajan1997/sympy,skidzo/sympy