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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 hash_args(*args, **kwargs):
 """Define a unique string for any set of representable args."""

    arg_string = '_'.join([str(arg) for arg in args])
    kwarg_string = '_'.join([str(key) + '=' + str(value)
                             for key, value in iteritems(kwargs)])
    combined = ':'.join([arg_string, kwarg_string])

    hasher = md5()
    hasher.update(b(combined))
    return hasher.hexdigest()