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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_dpi_group(dpi):
 # type: (int) -> Density """Get viewport density group from given dpi. :type dpi: int :return: viewport density group enum :rtype: Density """

    if dpi in range(0, 121):
        return Density.XLOW
    elif dpi in range(121, 161):
        return Density.LOW
    elif dpi in range(161, 241):
        return Density.MEDIUM
    elif dpi in range(241, 321):
        return Density.HIGH
    elif dpi in range(321, 481):
        return Density.XHIGH
    elif dpi >= 481:
        return Density.XXHIGH

    raise AskSdkException("Unknown dpi group value: {}".format(dpi))