dotted_array = [(1, 2, '.'), (4, 5, '.')]
list_of_signs = [['+', '-'], ['-', '-']]
coord_list = []
for idx1, list_of_sign in enumerate(list_of_signs):
    mylist = []
for idx2, tup in enumerate(dotted_array):
    mylist += [(tup[0], tup[1], list_of_signs[idx1][idx2])]
coord_list += mylist
print(coord_list)
In Python how do I use list comprehensions to iterate through a list of lists?