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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 process_seq(seq, material):
    '''Validate and process sequence inputs.

    :param seq: input sequence
    :type seq: str
    :param material: DNA, RNA, or peptide
    :type: str
    :returns: Uppercase version of `seq` with the alphabet checked by
              check_alphabet().
    :rtype: str

    '''
    check_alphabet(seq, material)
    seq = seq.upper()
    return seq