Translate Python AST into GLSL code.

    root: an ast.FunctionDef object

    Return a list of strings, where each string is a line of GLSL
    code.

def py_to_glsl(root):
    """Translate Python AST into GLSL code.

    root: an ast.FunctionDef object

    Return a list of strings, where each string is a line of GLSL
    code.
    """
    atg = AstToGlsl()
    code = atg.visit(root)
    return code.lines