def x_repes (f,n):
'''
>>> x_repes([4, 2, 5, 4, 5, 2, 3, 1], 2)
[4, 2]
>>> x_repes([4, 2, 5, 4, 5, 2, 3, 1], 4)
[]
>>> x_repes([4, 2, 5, 4, 5, 2, 3, 1], 3)
[4, 2, 5]
>>> x_repes([1, 1, 1, 1, 1, 1], 3)
[]
>>> x_repes(['good','bye','hello','good','bye'], 2)
['good', 'bye']
'''
lst = f
cont = 0
res = []
for elem in lst:
if lst.count(elem) >= 2 and elem not in res:
res.append(elem)
if len(res) == n:
return res
return []
if __name__=='__main__':
import doctest
doctest.testmod(verbose=True)