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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 process_form(self, instance, field, form, empty_marker=None, emptyReturnsMarker=False):
 """ Basic impl for form processing in a widget plus allowing empty values to be saved """


        # a poor workaround for Plone repeating itself.
        # XXX this is important XXX
        key = field.getName() + '_value'
        if key in instance.REQUEST:
            return instance.REQUEST[key], {}
        value = form.get(field.getName(), empty_marker)
        # When a recordswidget's visibility is defined as hidden
        # '...visible={'view': 'hidden', 'edit': 'hidden'},...' the template
        # displays it as an input field with the attribute 'value' as a string
        # 'value="[{:},{:}]"'. This makes the system save the content of the
        # widget as the string instead of a dictionary inside a list, so we
        # need to check if the variable contains a python object as a string.
        if value and value is not empty_marker and isinstance(value, str):
            import ast
            try:
                value = ast.literal_eval(form.get(field.getName()))
            except:
                # cannot resolve string as a list!
                return empty_marker

        if not value:
            return value, {}
        if value is empty_marker:
            return empty_marker
        if emptyReturnsMarker and value == '':
            return empty_marker

        # we make sure that empty "value" inputs are saved as "" empty string.
        for i in range(len(value)):
            value[i] = dict(value[i])
            if 'value' not in value[i]:
                value[i]['value'] = ''

        instance.REQUEST[key] = value
        return value, {}