def fun (a,x):
    a=[]
    m=a/x
    a.append(x)
    return a
fun([1,2,3,4,5,6,7], 3)

 def fun(a, x):
    result = []
    for value in a:
        if not value %x:
            result.append(value)
    return result

 [value for value in a if not value % x]

 >>> def fun(a, x):
...     result = []
...     i = a.pop()
...     if not i%x:
...         result.append(i)
...     if a:
...         result += fun(a, x)
...     return result
... 
>>> fun([1,2,3,4,5,6,7], 3)
[6, 3]

 #
func = lambda itr, spc: filter(lambda x: not x%spc, itr)