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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 to_creator(self, for_modify=False):
 """ Returns a dict object suitable for a 'CreateSignature'. A signature object for creation is like : <signature name="unittest"> <content type="text/plain">My signature content</content> </signature> which is : { 'name' : 'unittest', 'content': { 'type': 'text/plain', '_content': 'My signature content' } } Note that if the contenttype is text/plain, the content with text/html will be cleared by the request (for consistency). """

        signature = {}

        if for_modify:
            try:
                # we should have an ID
                signature['id'] = self.id
            except AttributeError:
                raise AttributeError('a modify request should specify an ID')
            # Case where we change or set a name
            if hasattr(self, 'name'):
                signature['name'] = self.name

        else:
            # a new signature should have a name
            signature['name'] = self.name

        if self.has_content():
            # Set one, flush the other (otherwise, we let relief behind...)
            if self._contenttype == 'text/plain':
                plain_text = self._content
                html_text = ''
            else:
                html_text = self._content
                plain_text = ''

            content_plain = {'type': 'text/plain', '_content': plain_text}
            content_html = {'type': 'text/html', '_content': html_text}

            signature['content'] = [content_plain, content_html]

        else:
            # A creation request should have a content
            if not for_modify:
                raise AttributeError(
                    'too little information on signature, '
                    'run setContent before')

        return signature