>>>globals = {'x':7,
.....: 'y':10,
.....: 'names':['aa','bb','cc']
.....: }
>>>locals = {}
>>>a = eval("3*x+4*y",globals,locals)
>>>print a
61
>>>exec("for i in names: print i",globals,locals)
aa
bb
cc
>>>globals = {'x':7,
.....: 'y':10,
.....: 'names':['aa','bb','cc']
.....: }
>>>locals = {}
>>>a = eval("3*x+4*y",globals,locals)
>>>print a
61
>>>exec("for i in names: print i",globals,locals)
aa
bb
cc