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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 _return_fieldset(self, fieldset):
 """ This function became a bit messy, since it needs to deal with two cases. 1) No fieldset, which is represented as an integer 2) A fieldset """

        collapsible = None
        description = None
        try:
            # Make sure strings with numbers work as well, do this
            int(str(fieldset))
            title = None
        except ValueError:
            if fieldset.count("|") > 1:
                raise ImproperlyConfigured(
                    "The fieldset name does not "
                    "support more than one | sign. "
                    "It's meant to separate a "
                    "fieldset from its description."
                )

            title = fieldset
            if "|" in fieldset:
                title, description = fieldset.split("|")
            if fieldset and (fieldset[0] in "-+"):
                if fieldset[0] == "-":
                    collapsible = "closed"
                else:
                    collapsible = "open"
                title = title[1:]

        return {
            "title": title,
            "description": description,
            "collapsible": collapsible,
        }