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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 _get_space_character_free_column_resolvers(self):
 """Return the space character free column resolvers of a dataframe. Column names with spaces are 'cleaned up' so that they can be referred to by backtick quoting. Used in :meth:`DataFrame.eval`. """

        from pandas.core.computation.common import _remove_spaces_column_name

        return {_remove_spaces_column_name(k): v for k, v
                in self.iteritems()}