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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 get_b_wiggle(x, y, y_int):
 """returns instantaneous slope from the ratio of NRM lost to TRM gained at the ith step"""

    if x == 0:
        b_wiggle = 0
    else:
        b_wiggle = old_div((y_int - y), x)
    return b_wiggle