<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def relations_dict(rel_lst):
 """constructs a relation's dictionary from a list that describes amphidromus relations between objects :param list rel_lst: a relationships list of the form [[a,b],[c, a, b]] # can include duplicates :returns: a dictionary :Example: {'a': ['x', 'c', 'b', 'y'], 'c': ['a', 'b'], 'b': ['a', 'c'], 'y': ['a', 'x', 'z'], 'x': ['a', 'z', 'y'], 'z': ['y', 'x']} """

    dc = {}
    for c in rel_lst:
        for i in c:
            for k in c:
                dc.setdefault(i, [])
                dc[i].append(k)
    do = {}
    for k in list(dc.keys()):
        if dc[k]:
            vl = list(set(dc[k]))   # remove duplicates
            vl.remove(k)
            do[k] = vl
    return do