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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 update_lincs_proteins():
 """Load the csv of LINCS protein metadata into a dict. Produces a dict keyed by HMS LINCS protein ids, with the metadata contained in a dict of row values keyed by the column headers extracted from the csv. """

    url = 'http://lincs.hms.harvard.edu/db/proteins/'
    prot_data = load_lincs_csv(url)
    prot_dict = {d['HMS LINCS ID']: d.copy() for d in prot_data}
    assert len(prot_dict) == len(prot_data), "We lost data."
    fname = os.path.join(path, 'lincs_proteins.json')
    with open(fname, 'w') as fh:
        json.dump(prot_dict, fh, indent=1)