Description

When using the HECClient, trying to list the names of the available tables raises a ValueError regarding an invalid token. Below is the traceback in the hopes it will be of some use:

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-48-d2712761b82a> in <module>
----> 1 hc.select_table()

~/.bin/miniconda3/envs/presage/lib/python3.9/site-packages/sunpy/net/helio/hec.py in select_table(self)
    257         >>> hc.select_table()  # doctest: +SKIP
    258         """
--> 259         tables = self.get_table_names()
    260         table_list = [t[0] for t in tables if len(t[0]) > 0]
    261         table_list.sort()

~/.bin/miniconda3/envs/presage/lib/python3.9/site-packages/sunpy/net/helio/hec.py in get_table_names(self)
    234         """
    235         results = self.hec_client.service.getTableNames()
--> 236         tables = votable_handler(etree.tostring(results))
    237         return tables.array
    238 

~/.bin/miniconda3/envs/presage/lib/python3.9/site-packages/sunpy/net/helio/hec.py in votable_handler(xml_table)
     47     fake_file = io.BytesIO()
     48     fake_file.write(xml_table)
---> 49     votable = parse_single_table(fake_file)
     50     for i in range(len(votable.array)):
     51         item = votable.array[i][0]

~/.bin/miniconda3/envs/presage/lib/python3.9/site-packages/astropy/io/votable/table.py in parse_single_table(source, **kwargs)
    183         kwargs['table_number'] = 0
    184 
--> 185     votable = parse(source, **kwargs)
    186 
    187     return votable.get_first_table()

~/.bin/miniconda3/envs/presage/lib/python3.9/site-packages/astropy/utils/decorators.py in wrapper(*args, **kwargs)
    533                     warnings.warn(message, warning_type, stacklevel=2)
    534 
--> 535             return function(*args, **kwargs)
    536 
    537         return wrapper

~/.bin/miniconda3/envs/presage/lib/python3.9/site-packages/astropy/io/votable/table.py in parse(source, columns, invalid, verify, chunk_size, table_number, table_id, filename, unit_format, datatype_mapping, _debug_python_based_parser)
    164             source,
    165             _debug_python_based_parser=_debug_python_based_parser) as iterator:
--> 166         return tree.VOTableFile(
    167             config=config, pos=(1, 1)).parse(iterator, config)
    168 

~/.bin/miniconda3/envs/presage/lib/python3.9/site-packages/astropy/io/votable/tree.py in parse(self, iterator, config)
   3570             'GROUP': self._add_group}
   3571 
-> 3572         for start, tag, data, pos in iterator:
   3573             if start:
   3574                 tag_mapping.get(tag, self._add_unknown_tag)(

ValueError: 395:1: not well-formed (invalid token)

Steps to Reproduce

from sunpy.net.helio import hec

hc = hec.HECClient()
print(hc.get_table_names())

System Details

General
#######
OS: Debian GNU/Linux 11 bullseye (Linux 5.10.0-9-amd64)
Arch : 64bit, ()
SunPy : 3.0.1

Required Dependices
###################
numpy: 1.20.3
parfive: 1.5.0
astropy: 4.2.1

Optional Dependices
###################
asdf: Missing, need asdf>=2.6.0; extra == "all"
beautifulsoup4: 4.10.0
dask: 2021.8.1
drms: 0.6.2
glymur: 0.9.4
h5netcdf: 0.11.0
h5py: 3.2.1
matplotlib: 3.4.2
pandas: 1.3.3
python-dateutil: 2.8.2
scikit-image: 0.18.1
scipy: 1.7.1
sqlalchemy: 1.4.22
tqdm: 4.62.2
zeep: 4.1.0