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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_smallest_compound_id(compounds_identifiers):
 """ Return the smallest KEGG compound identifier from a list. KEGG identifiers may map to compounds, drugs or glycans prefixed respectively with "C", "D", and "G" followed by at least 5 digits. We choose the lowest KEGG identifier with the assumption that several identifiers are due to chirality and that the lower one represents the more common form. Parameters compounds_identifiers : list A list of mixed KEGG identifiers. Returns ------- str The KEGG compound identifier with the smallest number. Raises ------ ValueError When compound_identifiers contains no KEGG compound identifiers. """

    return min((c for c in compounds_identifiers if c.startswith("C")),
               key=lambda c: int(c[1:]))