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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 validate_allowed_values(allowed_values, value):
 """Support a variable defining which values it allows. Args: allowed_values (Optional[list]):
 A list of allowed values from the variable definition value (obj):
 The object representing the value provided for the variable Returns: bool: Boolean for whether or not the value is valid. """

    # ignore CFNParameter, troposphere handles these for us
    if not allowed_values or isinstance(value, CFNParameter):
        return True

    return value in allowed_values