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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 _readedf_extractline(left, right):
 """Helper function to interpret lines in an EDF file header. """

    functions = [int, float, lambda l:float(l.split(None, 1)[0]),
                 lambda l:int(l.split(None, 1)[0]),
                 dateutil.parser.parse, lambda x:str(x)]
    for f in functions:
        try:
            right = f(right)
            break
        except ValueError:
            continue
    return right