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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def nsmap(self):
 """ Returns the current namespace mapping as a dictionary there are several problems with the map and we try to guess a few things here: 1) a URI can be mapped by many prefixes, so it is to decide which one to take 2) a prefix might map to an empty string (some packers) 3) uri+prefix mappings might be included several times 4) prefix might be empty """


        NSMAP = dict()
        # solve 3) by using a set
        for k, v in set(self.namespaces):
            s_prefix = self.sb[k]
            s_uri = self.sb[v]
            # Solve 2) & 4) by not including
            if s_uri != "" and s_prefix != "":
                # solve 1) by using the last one in the list
                NSMAP[s_prefix] = s_uri

        return NSMAP