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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 ricker(f, length, dt):
 """ A Ricker wavelet. Args: f (float):
 frequency in Haz, e.g. 25 Hz. length (float):
 Length in s, e.g. 0.128. dt (float):
 sample interval in s, e.g. 0.001. Returns: tuple. time basis, amplitude values. """

    t = np.linspace(-int(length/2), int((length-dt)/2), int(length/dt))
    y = (1. - 2.*(np.pi**2)*(f**2)*(t**2))*np.exp(-(np.pi**2)*(f**2)*(t**2))
    return t, y