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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 pileup_reads_at_position(samfile, chromosome, base0_position):
 """ Returns a pileup column at the specified position. Unclear if a function like this is hiding somewhere in pysam API. """


    # TODO: I want to pass truncate=True, stepper="all"
    # but for some reason I get this error:
    #      pileup() got an unexpected keyword argument 'truncate'
    # ...even though these options are listed in the docs for pysam 0.9.0
    #
    for column in samfile.pileup(
            chromosome,
            start=base0_position,
            end=base0_position + 1):

        if column.pos != base0_position:
            # if this column isn't centered on the base before the
            # variant then keep going
            continue

        return column.pileups

    # if we get to this point then we never saw a pileup at the
    # desired position
    return []