Removed the test for f(x) replaced by SF(x, 0, -1).
Removed the test for f(x) replaced by SF(x, 0, -1).

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