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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 round_down(x, decimal_places):
 """ Round a float down to decimal_places. Parameters x : float decimal_places : int Returns ------- rounded_float : float Examples -------- 1.234 1.23 """

    from math import floor
    d = int('1' + ('0' * decimal_places))
    return floor(x * d) / d