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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 iscm_md_append_array(self, arraypath, member):
 """ Append a member to a metadata array entry """

        array_path = string.split(arraypath, ".")
        array_key = array_path.pop()
        current = self.metadata
        for k in array_path:
            if not current.has_key(k):
                current[k] = {}
            current = current[k]
        if not current.has_key(array_key):
            current[array_key] = []
        if not type(current[array_key]) == list:
            raise KeyError("%s doesn't point to an array" % arraypath)
        current[array_key].append(member)