added method to convert to expressions
added method to convert to expressions

kaushik94/sympy,souravsingh/sympy,rahuldan/sympy,aktech/sympy,skidzo/sympy,chaffra/sympy,chaffra/sympy,madan96/sympy,madan96/sympy,rahuldan/sympy,sampadsaha5/sympy,kaushik94/sympy,kaushik94/sympy,jaimahajan1997/sympy,jaimahajan1997/sympy,skidzo/sympy,madan96/sympy,aktech/sympy,chaffra/sympy,jaimahajan1997/sympy,skidzo/sympy,drufat/sympy,postvakje/sympy,postvakje/sympy,yashsharan/sympy,sampadsaha5/sympy,postvakje/sympy,aktech/sympy,yashsharan/sympy,souravsingh/sympy,rahuldan/sympy,drufat/sympy,yashsharan/sympy,souravsingh/sympy,drufat/sympy,sampadsaha5/sympy