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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_column_metadata(gctx_file_path, convert_neg_666=True):
 """ Opens .gctx file and returns only column metadata Input: Mandatory: - gctx_file_path (str):
 full path to gctx file you want to parse. Optional: - convert_neg_666 (bool):
 whether to convert -666 values to num Output: - col_meta (pandas DataFrame):
 a DataFrame of all column metadata values. """

    full_path = os.path.expanduser(gctx_file_path)
    # open file
    gctx_file = h5py.File(full_path, "r")
    col_dset = gctx_file[col_meta_group_node]
    col_meta = parse_metadata_df("col", col_dset, convert_neg_666)
    gctx_file.close()
    return col_meta