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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 merge_enums(xml):
    '''merge enums between XML files'''
    emap = {}
    for x in xml:
        newenums = []
        for enum in x.enum:
            if enum.name in emap:
                emapitem = emap[enum.name]
                # check for possible conflicting auto-assigned values after merge
                if (emapitem.start_value <= enum.highest_value and emapitem.highest_value >= enum.start_value):
                    for entry in emapitem.entry:
                        # correct the value if necessary, but only if it was auto-assigned to begin with
                        if entry.value <= enum.highest_value and entry.autovalue == True:
                            entry.value = enum.highest_value + 1
                            enum.highest_value = entry.value
                # merge the entries
                emapitem.entry.extend(enum.entry)
                if not emapitem.description:
                    emapitem.description = enum.description
                print("Merged enum %s" % enum.name)
            else:
                newenums.append(enum)
                emap[enum.name] = enum
        x.enum = newenums
    for e in emap:
        # sort by value
        emap[e].entry = sorted(emap[e].entry,
                               key=operator.attrgetter('value'),
                               reverse=False)
        # add a ENUM_END
        emap[e].entry.append(MAVEnumEntry("%s_ENUM_END" % emap[e].name,
                                            emap[e].entry[-1].value+1, end_marker=True))