Category: Python Answers

Sometimes, we want to read a static file from inside a Python package.

In this article, we’ll look at how to read a static file from inside a Python package.

How to read a static file from inside a Python package?

To read a static file from inside a Python package, we can use the importlib.resources library.

For instance, we write

try:
    import importlib.resources as pkg_resources
except ImportError:
    import importlib_resources as pkg_resources

from . import templates 

template = pkg_resources.read_text(templates, 'temp_file')

to import our package with

from . import templates 

Then we read our static file with

template = pkg_resources.read_text(templates, 'temp_file')

We can also open the static file as a file with

template = pkg_resources.open_text(templates, 'temp_file')

Conclusion

To read a static file from inside a Python package, we can use the importlib.resources library.

Sometimes, we want to list all functions in a Python module.

In this article, we’ll look at how to list all functions in a Python module.

How to list all functions in a Python module?

To list all functions in a Python module, we can use the inspect module.

For instance, we write

from inspect import getmembers, isfunction
from somemodule import foo

print(getmembers(foo, isfunction))

to call getmembers with the foo module and the isfunction function to return a list of all functions in the foo module.

Conclusion

To list all functions in a Python module, we can use the inspect module.

Sometimes, we want to delete a file or folder in Python.

In this article, we’ll look at how to delete a file or folder in Python.

How to delete a file or folder in Python?

To delete a file or folder in Python, we can use the unlink method.

For instance, we write

file_to_rem = pathlib.Path("/tmp/file_name.txt")
file_to_rem.unlink()

to create a path object with pathlib.Path.

Then we call unlink to remove the item at the given path.

Conclusion

To delete a file or folder in Python, we can use the unlink method.

Sometimes, we want to pass variables to Python subprocess.Popen.

In this article, we’ll look at how to pass variables to Python subprocess.Popen.

How to pass variables to Python subprocess.Popen?

To pass variables to Python subprocess.Popen, we cann Popen with a list that has the variables we want to include.

For instance, we write

command = [
    "python",
    "mytool.py",
    "-a",
    servers[server]["address"],
    "-x",
    servers[server]["port"],
    "-p",
    servers[server]["pass"],
    "some",
    "additional",
    "command",
]
p = subprocess.Popen(command, shell=True, stdout=subprocess.PIPE)

to call Popen with the command list that has some static and dynamic command arguments.

Conclusion

To pass variables to Python subprocess.Popen, we cann Popen with a list that has the variables we want to include.

Sometimes, we want to correctly sort a string with a number inside with Python.

In this article, we’ll look at how to correctly sort a string with a number inside with Python.

How to correctly sort a string with a number inside with Python?

To correctly sort a string with a number inside with Python, we can create our own function to return the natural keys to sort by.

For instance, we write

import re


def atoi(text):
    return int(text) if text.isdigit() else text


def natural_keys(text):
    return [atoi(c) for c in re.split(r"(\d )", text)]


alist = [
    "something1",
    "something12",
    "something17",
    "something2",
    "something25",
    "something29",
]

alist.sort(key=natural_keys)
print(alist)

to create the atoi function that return the text convert to an int if text is all digits.

Otherwise, we return text.

Then we define the natural_keys function to return the natural keys by returning a list that has the values returned by atoi after splitting the text value by a digit.

Next, we call alist.sort with the key argument set to naturali_keys to sort alist in place by the natural keys.

Conclusion

To correctly sort a string with a number inside with Python, we can create our own function to return the natural keys to sort by.