bug: Error when loading an mf6 model with time series package

[OnnoEbbens]

Describe the bug
When I try to read a model using flopy.mf6.MFSimulation.load I get a MFDataException error when it tries to read the time series data.

To Reproduce
Run this notebook with the code below at the end:

sim.write_simulation()
sim2 = flopy.mf6.MFSimulation.load("mfsim.nam", sim_ws=workspace, exe_name="mf6")

Full error

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mfdatautil.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mfdatautil.py) in convert_data(data, data_dimensions, data_type, data_item, sub_amt)
     80                     data = data.replace("d", "e")
---> 81                 return float(data)
     82             except (ValueError, TypeError):

ValueError: could not convert string to float: 'tiees'

During handling of the above exception, another exception occurred:

ValueError                                Traceback (most recent call last)
[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mfdatautil.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mfdatautil.py) in convert_data(data, data_dimensions, data_type, data_item, sub_amt)
     83                 try:
---> 84                     return float(PyListUtil.clean_numeric(data))
     85                 except (ValueError, TypeError):

ValueError: could not convert string to float: ''

During handling of the above exception, another exception occurred:

MFDataException                           Traceback (most recent call last)
[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mffileaccess.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mffileaccess.py) in read_list_data_from_file(self, file_handle, storage, current_key, current_line, data_line, store_internal)
   1223         try:
-> 1224             data_line = self.load_list_line(
   1225                 storage,

[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mffileaccess.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mffileaccess.py) in load_list_line(self, storage, arr_line, line_num, data_loaded, build_type_list, current_key, data_index_start, data_set, ignore_optional_vars, data_line, zero_based)
   1911                                         unknown_repeats,
-> 1912                                     ) = self._append_data_list(
   1913                                         storage,

[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mffileaccess.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mffileaccess.py) in _append_data_list(self, storage, data_item, arr_line, arr_line_len, data_index, var_index, repeat_count, current_key, data_line, add_to_last_line, zero_based)
   2222                 else:
-> 2223                     data_converted = convert_data(
   2224                         arr_line[data_index],

[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mfdatautil.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mfdatautil.py) in convert_data(data, data_dimensions, data_type, data_item, sub_amt)
     91                     type_, value_, traceback_ = sys.exc_info()
---> 92                     raise MFDataException(
     93                         data_dimensions.structure.get_model(),

MFDataException: An error occurred in data element "stress_period_data" model "gwf6" package "ghb". The error occurred while converting data in the "convert_data" method.
Additional Information:
(1) Data "stress_period_data" with value "tiees" can not be converted to float.

During handling of the above exception, another exception occurred:

MFDataException                           Traceback (most recent call last)
[c:\Users\oebbe\02_python\flopy\flopy\mf6\mfpackage.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/mfpackage.py) in load(self, block_header, fd, strict)
    885                         )
--> 886                     next_line = dataset.load(
    887                         line,

[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mfdatalist.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mfdatalist.py) in load(self, first_line, file_handle, block_header, pre_data_comments, external_file_info)
   2026         self._load_prep(block_header)
-> 2027         return super().load(
   2028             first_line,

[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mfdatalist.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mfdatalist.py) in load(self, first_line, file_handle, block_header, pre_data_comments, external_file_info)
   1398             )
-> 1399             result = file_access.load_from_package(
   1400                 first_line, file_handle, storage, pre_data_comments

[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mffileaccess.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mffileaccess.py) in load_from_package(self, first_line, file_handle, storage, pre_data_comments)
   1152                 self._data_line,
-> 1153             ) = self.read_list_data_from_file(
   1154                 file_handle,

[c:\Users\oebbe\02_python\flopy\flopy\mf6\data\mffileaccess.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/data/mffileaccess.py) in read_list_data_from_file(self, file_handle, storage, current_key, current_line, data_line, store_internal)
   1283                 type_, value_, traceback_ = sys.exc_info()
-> 1284                 raise MFDataException(
   1285                     struct.get_model(),

MFDataException: An error occurred in data element "stress_period_data" model "gwf6" package "ghb". The error occurred while loading data list from package file in the "read_list_data_from_file" method.
Additional Information:
(1) Data "stress_period_data" with value "tiees" can not be converted to float.
(2) Unable to process line 1 of data list: "  2 1 10  tides      15.00000000  Estuary-L2
"

During handling of the above exception, another exception occurred:

MFDataException                           Traceback (most recent call last)
[~\AppData\Local\Temp\ipykernel_15480\896463903.py](https://file+.vscode-resource.vscode-cdn.net/c%3A/Users/oebbe/02_python/flopy/~/AppData/Local/Temp/ipykernel_15480/896463903.py) in ()
      1 sim.write_simulation()
----> 2 sim2 = flopy.mf6.MFSimulation.load("mfsim.nam", sim_ws=workspace, exe_name="mf6")

[c:\Users\oebbe\02_python\flopy\flopy\mf6\modflow\mfsimulation.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/modflow/mfsimulation.py) in load(cls, sim_name, version, exe_name, sim_ws, strict, verbosity_level, load_only, verify_data, write_headers, lazy_io)
    782             if verbosity_level.value >= VerbosityLevel.normal.value:
    783                 print(f"  loading model {item[0].lower()}...")
--> 784             instance._models[item[2]] = model_obj.load(
    785                 instance,
    786                 instance.structure.model_struct_objs[item[0].lower()],

[c:\Users\oebbe\02_python\flopy\flopy\mf6\modflow\mfgwf.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/modflow/mfgwf.py) in load(cls, simulation, structure, modelname, model_nam_file, version, exe_name, strict, model_rel_path, load_only)
    125         load_only=None,
    126     ):
--> 127         return mfmodel.MFModel.load_base(
    128             simulation,
    129             structure,

[c:\Users\oebbe\02_python\flopy\flopy\mf6\mfmodel.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/mfmodel.py) in load_base(cls, simulation, structure, modelname, model_nam_file, mtype, version, exe_name, strict, model_rel_path, load_only)
    799                     print(f"    loading package {ftype}...")
    800                 # load package
--> 801                 instance.load_package(ftype, fname, pname, strict, None)
    802                 sim_data = simulation.simulation_data
    803                 if ftype == "dis" and not sim_data.max_columns_user_set:

[c:\Users\oebbe\02_python\flopy\flopy\mf6\mfmodel.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/mfmodel.py) in load_package(self, ftype, fname, pname, strict, ref_path, dict_package_name, parent_package)
   1864         )
   1865         try:
-> 1866             package.load(strict)
   1867         except ReadAsArraysException:
   1868             #  create ReadAsArrays package and load it instead

[c:\Users\oebbe\02_python\flopy\flopy\mf6\mfpackage.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/mfpackage.py) in load(self, strict)
   2670 
   2671         try:
-> 2672             self._load_blocks(fd_input_file, strict)
   2673         except ReadAsArraysException as err:
   2674             fd_input_file.close()

[c:\Users\oebbe\02_python\flopy\flopy\mf6\mfpackage.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/mfpackage.py) in _load_blocks(self, fd_input_file, strict, max_blocks)
   2847                         )
   2848 
-> 2849                         cur_block.load(
   2850                             block_header_info, fd_input_file, strict
   2851                         )

[c:\Users\oebbe\02_python\flopy\flopy\mf6\mfpackage.py](file:///C:/Users/oebbe/02_python/flopy/flopy/mf6/mfpackage.py) in load(self, block_header, fd, strict)
    892                     )
    893                 except MFDataException as mfde:
--> 894                     raise MFDataException(
    895                         mfdata_except=mfde,
    896                         model=self._container_package.model_name,

MFDataException: An error occurred in data element "stress_period_data" model "tutorial03_mf6_data" package "ghb". The error occurred while loading data list from package file in the "read_list_data_from_file" method.
Additional Information:
(1) Data "stress_period_data" with value "tiees" can not be converted to float.
(2) Unable to process line 1 of data list: "  2 1 10  tides      15.00000000  Estuary-L2
"
(3) Error occurred while loading data "stress_period_data" in block "period" from file "C:\Users\oebbe\AppData\Local\Temp\tmpoziwbxlz\tutorial03_mf6_data.ghb".

Desktop (please complete the following information):

• OS: Windows
• Flopy version 3.4.1 & 3.3.6

[spaulins-usgs]

@OnnoEbbens, I just committed a PR to the develop branch that should fix this problem. Please use the develop branch of flopy and confirm that this fixes the issue.

[OnnoEbbens]

Thanks a lot!