How to import a class/function in google Colab from a .py file on google drive

Question:

I am trying to import a class from a .py file which is stored in my google drive.

Initially, I have mounted google drive as follows:

from google.colab import drive
drive.mount('/content/drive')

Then navigate into the destination folder using:

%cd "/content/drive/MyDrive/Autonomous_Driving/GRTP/clstm_lifelong/us1011/sgan-nsl"
!ls

It shows output like:

/content/drive/MyDrive/Autonomous_Driving/GRTP/clstm_lifelong/us1011/sgan-nsl
checkpoint.pkl        __pycache__           utils_wcgan_decompose.py
loss.mat          trained_models
model_wcgan_decompose.py  train_wcgan_decompose.py

Now in that model_wcgan_decompose.py file of the drive there was some class named highwayNet_d, highwayNet_g_compose, highwayNet. Now I am trying to import the class for my purpose using:

from model_wcgan_decompose import highwayNet_d

but it shows error like:

ImportError                               Traceback (most recent call last)
<ipython-input-26-256c2191a0a5> in <cell line: 9>()
      7 #import model_wcgan_decompose
      8 
----> 9 from model_wcgan_decompose import highwayNet_d
     10 
     11 

ImportError: cannot import name 'highwayNet_d' from 'model_wcgan_decompose' (/content/drive/MyDrive/Autonomous_Driving/GRTP/clstm_lifelong/us1011/sgan-nsl/model_wcgan_decompose.py)

Please suggest how can I fix it?

Asked By: Kanchon Gharami

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Source

Answers:

We can open some_file of code with codecs, use json to load it, and make it string so we can execute some_code_in_string; the important part is that we change the 'execution_count' in its dictionary from None to 1 (or however many times we want it to execute the code).

So here in 'SomeClass.ipynb' I have the following code:

class SomeClass:
    def __init__(self):
        print(f'init {self.__class__.__name__}')
        self.foo = 0
SomeClass()

In another file, we can run:

import codecs
import json

some_file = codecs.open('/content/drive/My Drive/Colab Notebooks/SomeClass.ipynb', 'r')
some_file = some_file.read()
some_file = json.loads(some_file)
some_file['cells'][0]['execution_count'] = 1
some_code_in_string = ''
for code_in_file in some_file['cells']:
    for _code_in_file in code_in_file['source']:
        some_code_in_string += _code_in_file
        some_code_in_string += 'n'
exec(some_code_in_string)

Outputs:

init SomeClass

Now if some_file is 'SomeClass.py' it’s a bit trickier since we have to find where the first line of code actually begins:

import codecs

some_file = codecs.open('/content/drive/My Drive/Colab Notebooks/SomeClass.py', 'r')
some_file = some_file.read()
some_code_in_string = some_file[some_file[some_file.find('https'):].find('"') + 3 + some_file.find('https') + some_file[some_file[some_file.find('https'):].find('"') + 3 + some_file.find('https')].find(' ') + 3:]
exec(some_code_in_string)

Outputs:

init SomeClass

Either way, the goal is to get some_code_in_string correctly formatted like:

some_code_in_string = '''
class SomeClass:
    def __init__(self):
        print(f'init {self.__class__.__name__}')
        self.foo = 0
SomeClass()
'''

so that we can execute it.

Answered By: Ori Yarden