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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 combine(self, pattern, variable):
 """Combine a pattern and variable parts to be a line string again."""

        inter_zip = izip_longest(variable, pattern, fillvalue='')
        interleaved = [elt for pair in inter_zip for elt in pair]
        return ''.join(interleaved)