def simplify_gamma_expression(expression):
    (extracted_expr, residual_expr) = extract_type_tens(expression, GammaMatrix)
    res_expr = _simplify_single_line(extracted_expr)
    return (res_expr * residual_expr)
def simplify_gamma_expression(expression):
    (extracted_expr, residual_expr) = extract_type_tens(expression, GammaMatrix)
    res_expr = _simplify_single_line(extracted_expr)
    return (res_expr * residual_expr)