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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 gridrange(start, end, step):
 """Generate a grid of complex numbers"""

    for x in frange(start.real, end.real, step.real):
        for y in frange(start.imag, end.imag, step.imag):
            yield x + y * 1j