Installation of Fiona 1.8.20 not compatible with libgdal 3.3.0 on Ubuntu 20.04

[kyri-petrou]

Issue

It's not possible to install fiona 1.8.20 with libgdal 3.3.0. I believe that this is not expected since fiona 1.8.20 is supposed to support libgdal 3.3.0.

I understand that Fiona is still available with libgdal < 3.3, but this prevents us from using pdal 2.3.0. Please let me know if there's any way I can offer help to resolve this issue faster!

Steps to reproduce (Note: The same issue exists with all other Python 3.x versions

conda create -n python=3.9 fiona==1.8.20 libgdal==3.3

Output:

Collecting package metadata (current_repodata.json): done
Solving environment: failed with repodata from current_repodata.json, will retry with next repodata source.
Collecting package metadata (repodata.json): done
Solving environment: | 
Found conflicts! Looking for incompatible packages.
This can take several minutes.  Press CTRL-C to abort.
failed                                                                                                                                                                                                                                                                   

UnsatisfiableError: The following specifications were found to be incompatible with each other:

Output in format: Requested package -> Available versions

Package libgdal conflicts for:
libgdal=3.3.0
fiona=1.8.20 -> gdal -> libgdal[version='2.4.1|2.4.1|2.4.1|2.4.2|2.4.2|2.4.2|2.4.2|2.4.2|2.4.3|2.4.3|2.4.4|2.4.4|3.0.1|3.0.1|3.0.1|3.0.1|3.0.2|3.0.2|3.0.2|3.0.2|3.0.2|3.0.2|3.0.2|3.0.2|3.0.2|3.0.3|3.0.4|3.0.4|3.0.4|3.0.4|3.0.4|3.0.4|3.0.4|3.0.4|3.0.4|3.0.4|3.0.4|3.1.0|3.1.0|3.1.0|3.1.0|3.1.1|3.1.1|3.1.1|3.1.2|3.1.2|3.1.2|3.1.2|3.1.2|3.1.3|3.1.3|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.1.4|3.2.0|3.2.1|3.2.1|3.2.1|3.2.1|3.2.1|3.2.1|3.2.1|3.2.1|3.2.1|3.2.1|3.2.2|3.2.2|3.2.2|3.2.2|3.2.2|3.2.2|3.2.2|3.2.2|3.3.0',build='hc4f5fd6_10|hbef8c27_4|h524de44_5|h182c168_7|h182c168_8|h2f07a13_9|h2bea7cd_7|h3d260b8_1|hc7cfd23_2|h30a29e3_5|h20022a4_8|h20022a4_0|h20022a4_0|h4f4a046_5|hbd881e9_7|he6a97d6_10|h0b4441a_2|h4ed0dcf_0|h6687615_1|h6687615_0|hb2a6f5f_1|h670eac6_4|h670eac6_1|h670eac6_0|h02eeb80_2|h744752d_4|hbde00c8_6|h38ff51b_8|h804b7da_10|h928efbf_12|hbf32332_13|h679344c_14|h8f005ca_17|h24f7f85_0|h96b6e7a_2|h6636813_8|h804b7da_9|hbf32332_0|h679344c_1|h8f005ca_3|h4dcd70e_2|h8f005ca_7|h4dcd70e_6|h679344c_5|hbf32332_4|hbf32332_3|h928efbf_2|h78c8158_1|h804b7da_0|h38ff51b_7|he6eed4e_6|hbde00c8_5|h0a4f56a_4|h744752d_3|h52563cd_1|h2812452_0|h4dcd70e_16|h3215d8d_15|h78c8158_11|h6636813_9|he6eed4e_7|h0a4f56a_5|h96b6e7a_3|h50e41a3_1|h670eac6_0|hb2a6f5f_3|hf6fc319_2|h6687615_2|h4ed0dcf_3|h2e1b11c_1|he6a97d6_0|h99f9e9c_9|h99f9e9c_8|h3dfc09a_6|h9e6407a_4|h94bbfbd_3|hce44138_2|h022d3c0_1|hbe56659_7|hefdf094_6|h852c1c0_4|h5534617_3|h3d260b8_0|h3d260b8_10|hcf75f94_9|hf47eb90_8|h5439ffd_1|h2b6fda6_0|hd53ac37_8|h04a3d72_6|ha50d65d_9|heae24aa_8']
fiona=1.8.20 -> libgdal[version='>=3.2.2,<3.3.0a0']

Package ca-certificates conflicts for:
libgdal=3.3.0 -> openssl[version='>=1.1.1k,<1.1.2a'] -> ca-certificates
python=3.9 -> openssl[version='>=1.1.1k,<1.1.2a'] -> ca-certificates

Package libffi conflicts for:
fiona=1.8.20 -> python[version='>=3.6,<3.7.0a0'] -> libffi[version='>=3.2.1,<3.3.0a0|>=3.3,<3.4.0a0']
python=3.9 -> libffi[version='>=3.2.1,<3.3.0a0|>=3.3,<3.4.0a0']

Package python conflicts for:
fiona=1.8.20 -> attrs[version='>=17'] -> python[version='2.7.*|3.5.*|3.6.*|>=2.7,!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*|3.4.*|>=3|<4.0|>=2.7,<2.8.0a0|>=3.5,<3.6.0a0|3.7.*|3.8.*|3.9.*']
fiona=1.8.20 -> python[version='>=3.6,<3.7.0a0|>=3.7,<3.8.0a0|>=3.8,<3.9.0a0|>=3.9,<3.10.0a0']
python=3.9

[jorisvandenbossche]

For people ending up here -> https://github.com/conda-forge/fiona-feedstock/pull/179 tries to fix this