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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_model(input_dim):
 """Create and compile simple model."""

    model = Sequential()
    model.add(Dense(100, input_dim=input_dim, activation='sigmoid'))
    model.add(Dense(1))
    model.compile(loss='mean_squared_error', optimizer='SGD')
    return model