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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 base10_integer_to_basek_string(k, x):
 """Convert an integer into a base k string."""

    if not (2 <= k <= max_k_labeled):
        raise ValueError("k must be in range [2, %d]: %s"
                         % (max_k_labeled, k))
    return ((x == 0) and numerals[0]) or \
        (base10_integer_to_basek_string(k, x // k).\
         lstrip(numerals[0]) + numerals[x % k])