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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_snapshot(name, suffix, array):
    '''Private function to check snapshot'''
    snapshot = name + '.' + suffix
    try:
        for snap in array.get_volume(name, snap=True):
            if snap['name'] == snapshot:
                return snapshot
    except purestorage.PureError:
        return None