尝试从environment.yml文件创建环境时出现“ResolvePackageNotFound”错误

Question

在克隆了github存储库后，我试图从这个environment.yml文件创建一个环境，但它一直说创建失败是因为以下错误：

ResolvePackageNotFound:
      - dbus==1.13.14=h517e14e_0
      - gettext==0.19.8.1=hb0f4f8b_2
      - markupsafe==1.1.1=py38h1de35cc_0
      - pandas==1.0.3=py38h6c726b0_0
      - intel-openmp==2019.4=233
      - mkl_fft==1.0.15=py38h5e564d8_0
      - glib==2.63.1=h70d4741_1
      - pyzmq==18.1.1=py38h0a44026_0
      - zstd==1.4.4=h1990bb4_3
      - libffi==3.3=h0a44026_1
      - scipy==1.4.1=py38h44e99c9_0
      - llvm-openmp==10.0.0=h28b9765_0
      - lz4-c==1.9.2=h0a44026_0
      - libcxx==10.0.0=1
      - scikit-learn==0.22.1=py38h27c97d8_0
      - numpy==1.18.1=py38h7241aed_0
      - libpng==1.6.37=ha441bb4_0
      - qt==5.9.7=h468cd18_1
      - zeromq==4.3.1=h0a44026_3
      - ncurses==6.2=h0a44026_1
      - zlib==1.2.11=h1de35cc_3
      - matplotlib-base==3.1.3=py38h9aa3819_0
      - cffi==1.14.0=py38hc512035_1
      - pcre==8.43=h0a44026_0
      - pillow==7.1.2=py38h4655f20_0
      - python==3.8.3=h26836e1_1
      - ptyprocess==0.6.0=py38_0
      - sqlite==3.31.1=h5c1f38d_1
      - ninja==1.9.0=py38h04f5b5a_0
      - mkl-service==2.3.0=py38hfbe908c_0
      - mistune==0.8.4=py38h1de35cc_1000
      - libtiff==4.1.0=hcb84e12_1
      - xz==5.2.5=h1de35cc_0
      - kiwisolver==1.2.0=py38h04f5b5a_0
      - appnope==0.1.0=py38_0
      - expat==2.2.6=h0a44026_0
      - tornado==6.0.4=py38h1de35cc_1
      - brotlipy==0.7.0=py38h64e0658_1000
      - mkl==2019.4=233
      - cryptography==2.9.2=py38hb761dab_0
      - icu==58.2=h0a44026_3
      - sip==4.19.8=py38h0a44026_0
      - readline==8.0=h1de35cc_0
      - libsodium==1.0.16=h3efe00b_0
      - numpy-base==1.18.1=py38h3304bdc_1
      - libedit==3.1.20181209=hb402a30_0
      - pyrsistent==0.16.0=py38h1de35cc_0
      - tk==8.6.8=ha441bb4_0
      - jpeg==9b=he5867d9_2
      - libiconv==1.16=h1de35cc_0
      - pyqt==5.9.2=py38h655552a_2
      - libgfortran==3.0.1=h93005f0_2
      - openssl==1.1.1g=h1de35cc_0
      - pytorch==1.5.0=py3.8_0
      - mkl_random==1.1.1=py38h959d312_0
      - freetype==2.9.1=hb4e5f40_0

environment.yml文件如下所示：

name: rewards
channels:
  - pytorch
  - conda-forge
  - defaults

dependencies:
  - appnope=0.1.0=py38_0
  - attrs=19.3.0=py_0
  - backcall=0.1.0=py38_0
  - blas=1.0=mkl

...

我应该如何着手解决此错误？我已经尝试添加一个pip语句，但是，考虑到我正在创建一个conda环境而不是pip环境，我不知道这是否是下载所有软件包的正确方法。为什么这个错误也会发生