Pip install ошибка синтаксиса

As @sinoroc suggested correct way of installing a package via pip is using separate process since pip may cause closing a thread or may require a restart of interpreter to load new installed package so this is the right way of using the API: subprocess.check_call([sys.executable, '-m', 'pip', 'install', 'SomeProject']) but since Python allows to access internal API and you know what you’re using the API for you may want to use internal API anyway eg. if you’re building own GUI package manager with alternative resourcess like https://www.lfd.uci.edu/~gohlke/pythonlibs/

Following soulution is OUT OF DATE, instead of downvoting suggest updates. see https://github.com/pypa/pip/issues/7498 for reference.

UPDATE: Since pip version 10.x there is no more get_installed_distributions() or main method under import pip instead use import pip._internal as pip.

UPDATE ca. v.18 get_installed_distributions() has been removed. Instead you may use generator freeze like this:

from pip._internal.operations.freeze import freeze

print([package for package in freeze()])

# eg output ['pip==19.0.3']

If you want to use pip inside the Python interpreter, try this:

import pip

package_names=['selenium', 'requests'] #packages to install
pip.main(['install'] + package_names + ['--upgrade']) 
# --upgrade to install or update existing packages

If you need to update every installed package, use following:

import pip

for i in pip.get_installed_distributions():
    pip.main(['install', i.key, '--upgrade'])

If you want to stop installing other packages if any installation fails, use it in one single pip.main([]) call:

import pip

package_names = [i.key for i in pip.get_installed_distributions()]
pip.main(['install'] + package_names + ['--upgrade'])

Note: When you install from list in file with -r / --requirement parameter you do NOT need open() function.

pip.main(['install', '-r', 'filename'])

Warning: Some parameters as simple --help may cause python interpreter to stop.

Curiosity: By using pip.exe you actually use python interpreter and pip module anyway. If you unpack pip.exe or pip3.exe regardless it’s python 2.x or 3.x, inside is the SAME single file __main__.py:

# -*- coding: utf-8 -*-
import re
import sys

from pip import main

if __name__ == '__main__':
    sys.argv[0] = re.sub(r'(-script.pyw?|.exe)?$', '', sys.argv[0])
    sys.exit(main())

The pip package installer is only available from the command line. You’ll get the SyntaxError: invalid syntax error if you try to install a package via the Python interpreter or a Python program. When beginners try to install Python packages, one of the most common issues they see is SyntaxError: invalid syntax. We will examine a real-world scenario to demonstrate the issue at hand.

The command prompt area is where we run Python to launch the Python shell, but within it is a shell. How can we tell if we’re in the Python shell or the command prompt? We can simply confirm it.

When we execute the Python shell with the python command, we are in the Python shell, and three greater than signs will appear in the left corner. These three indicators indicate that the user is working in a different shell, in this case, the Python shell. Another method for newbies to recognize whether they are within the command prompt is to look for a drive name and a path name of your folder where your cursor blinks.

In this “PIP install Invalid Syntax” post, we will explore what causes the pip install improper syntax problem and what it means. We’ll review an example of this problem to show you how to correct it in your code.

What exactly is PIP?

PIP is a Python package installer. It lets you download, install, update, and uninstall software programs. Further, pip is usually installed by default on your system.

It’s important to understand that pip is a command-line utility, not a Python module. It will assist you in comprehending why this mistake arises and how to resolve it.

pip install invalid syntax

Python pip is a package installer written in Python. The pip tool allows you to download and install packages from the Python Package Index, which contains thousands of libraries with which you can work with your code.

The pip package manager has its command line interface. pip is not part of your Python installation. It is because pip is an installer rather than a program executing code.

In case these tools were bundled together, it would be more difficult for developers to install packages because the syntax used to start a Python application would also be used to install modules. It is a regular occurrence in programming environments. To install packages, Node.js uses npm. The latter node command is required to launch Node.js software.

What causes the “pip install invalid syntax” error?

When you try to call the pip command from within a Python interpreter or script, you get the “pip install invalid syntax” error. As previously stated, pip is a command-line utility for managing Python packages. You cannot, however, try to access it directly from a Python interpreter.

It’s the same as typing ls -la into the Python interpreter. As a result, the next steps will be geared towards reproducing this problem. Assume we wish to install the idna package with pip. Begin by launching the Python interpreter as:

It should provide us with a Python environment that is interactive. When we perform the pip install idna command in the session, we get the following error:

As we can see, we can’t use pip to install a package inside a Python interpreter.

What is the fix?

The solution is straightforward. Use the pip install command from a terminal window rather than the Python interpreter. Exit the Python interpreter session before installing the idna package with pip:

Once you’ve returned to your system’s shell, type:

Replace “idna” with the target package you want to install. The problem should be fixed, and your target package should be installed.

Example problem with Beautiful soup four library

In this section, we will install the Beautiful Soup 4 library (bs4) in a development environment. This library allows you to scrape a web page and obtain specific data. To begin, launch a Python 3 shell. We’ll complete all of our project work in this shell:

An interactive shell is launched, where we can enter our Python code.

Next, we’ll include the bs4 library in our code. Any external libraries we want to use must be imported before they can be used in a program or the shell. The following command will be used to import the bs4package:

from bs4 import BeautifulSoup

When we try to import our package, our code throws a ModuleNotFoundError. It implies we won’t be able to continue working on our program. Python is unable to discover the package modules required to write our program. Let’s resolve this issue by installing the bs4 library while still in the Python interactive interface as follows:

This command generates another error:

"SyntaxError: invalid syntax"

The pip command in the Python shell cannot be used to install bs4. By the way, the package installer for Python 3 packages is pip3.

The cause is that we attempted to use the Python interpreter to install the bs4 package. You can tell since we launched Python 3 with the python3 command and ran the pip3 install command. The reason for the latter is pip is not a Python keyword, so Python produces a pip install invalid syntax error. pip is a command-line utility that must be executed from a command-line shell.

To resolve this issue, we must first exit our Python shell:

The exit() instruction instructs Python to close the currently open interpreter. Then, using the command prompt, we can install bs4 as follows:

This program will download and install the pip library on our system. After this command has been executed, we may launch a new Python shell:

The bs4 library should be accessible to our new shell. As a result, we can put this to the test by importing bs4 into our code:

from bs4 import BeautifulSoup

There is no error. It indicates that the import was a success. Go ahead and now incorporate bs4 into your program.

Conclusion

When beginners try to install Python packages, one of the most common issues they see is SyntaxError: invalid syntax. In this article, we have examined two real-world scenarios to demonstrate the issue.

Congratulations! We discovered the cause of the “pip install improper syntax error” and how to fix it in this post.

pip install does not work when trying to install virtualenv, requests or pex on CentOS6. I am on python2.6 and pip 9.0.1. Can anyone tell me why is this happening?

(pex_build)[root@pex pex_build]# pip install virtualenv

Output:

Traceback (most recent call last):
  File "/opt/pex_build/bin/pip", line 7, in <module>
    from pip._internal import main
  File "/opt/pex_build/lib/python2.6/site-packages/pip/_internal/__init__.py", line 42, in <module>
    from pip._internal import cmdoptions
  File "/opt/pex_build/lib/python2.6/site-packages/pip/_internal/cmdoptions.py", line 16, in <module>
    from pip._internal.index import (
  File "/opt/pex_build/lib/python2.6/site-packages/pip/_internal/index.py", line 526
    {str(c.version) for c in all_candidates},
                      ^
SyntaxError: invalid syntax

Command:

(pex_build) [root@pex pex_build]# pip install requests pex

Output:

Traceback (most recent call last):
  File "/opt/pex_build/bin/pip", line 7, in <module>
    from pip._internal import main
  File "/opt/pex_build/lib/python2.6/site-packages/pip/_internal/__init__.py", line 42, in <module>
    from pip._internal import cmdoptions
  File "/opt/pex_build/lib/python2.6/site-packages/pip/_internal/cmdoptions.py", line 16, in <module>
    from pip._internal.index import (
  File "/opt/pex_build/lib/python2.6/site-packages/pip/_internal/index.py", line 526
    {str(c.version) for c in all_candidates},
                      ^
SyntaxError: invalid syntax

Also curl gives the similar error, when trying to get get-pip.py

Command:

(pex_build) [root@pex pex_build]# curl https://bootstrap.pypa.io/get-pip.py | python



% Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 1602k  100 1602k    0     0  7373k      0 --:--:-- --:--:-- --:--:-- 14.6M

Traceback (most recent call last):
  File "<stdin>", line 20636, in <module>
  File "<stdin>", line 197, in main
  File "<stdin>", line 82, in bootstrap
  File "/tmp/tmp5zrn_f/pip.zip/pip/_internal/__init__.py", line 42, in <module>
  File "/tmp/tmp5zrn_f/pip.zip/pip/_internal/cmdoptions.py", line 16, in <module>
  File "/tmp/tmp5zrn_f/pip.zip/pip/_internal/index.py", line 526
    {str(c.version) for c in all_candidates},
                      ^
SyntaxError: invalid syntax

Python supports different modules and packages that are used to perform various operations in fields like AI, Robotics, Machine Learning, etc. Some of the popular modules that are used in Python are Numpy, Pandas, OpenCV, TensorFlow, etc.

To use these modules, we need to install them in our Python using a different package manager. Python recommended a package manager named “pip” to install any module using simple commands. These commands are executed in cmd, bash, or PowerShell terminal; if these commands are executed in a Python script file, then the “SyntaxError” arises in the program.

This post will deliver a comprehensive guide on resolving the “pip install” SyntaxError in Python.

The given below points will be elaborated on in this article:

• Reason: Executing pip Install Command in Python Interpreter
• Solution 1: Use CMD to Install any Module in Python Using a pip
• Solution 2: Use PowerShell to Install any Module in Python Using a pip
• How to Use an Installed Module in Python?

Let’s begin with the first reason.

Reason: Executing pip Install Command in Python Interpreter

The “SyntaxError: invalid syntax” is invoked in Python when we try to use the “pip install” command to install a module in the Python script.

The above output shows “SyntaxError” because the user attempted to execute the “pip install” command in the Python file.

Solution 1: Use CMD to Install Any Module in Python Using a pip

To fix this “SyntaxError”, you need to use “CMD” or command prompt terminal to install any module using the “pip” package manager. To open cmd, press the “Windows Key + R” button and type cmd in the run dialog box.

Type cmd in the run dialog box and click on the “ok” button to open the cmd terminal.

After opening the command prompt, you can type the below command to install the “Flask” module in Python. By typing the specific pip command, you can download any module using the “pip” package manager. If you don’t have a pip, you can download and install it in your system by following this tutorial.

In our case, we installed the “Flask” module using the below command:

The above snippet verified that the “Flask” had been successfully installed in Python.

Solution 2: Use PowerShell to Install Any Module in Python Using a pip

The “PowerShell” can also be used to install any open-source module in Python using the “pip” package manager. To open the “PowerShell”, you can simply type the PowerShell in the start search bar and double-click on the icon to open it.

After opening PowerShell, you can type the below command to install the “Flask” module in Python.

The above snippet shows that the “Flask” module has been successfully installed in Python.

How to Use an Installed Module in Python?

To use an installed module in a Python program, you need to import the module at the program’s start. The “import” keyword is used along with the module’s name to import it into the program. After importing, you can access its function and use them in a program. The below code is used to import the “flask” library in Python:

Note: You can find the large collection of modules along with their installation “pip command” at this site.

After opening the site, type the module name at the search bar and select the latest version of your module.

Now copy the command and paste it into cmd or PowerShell to install the module:

That’s it from the pip install causes syntax error.

Conclusion

The “SyntaxError: invalid syntax” occurs when the executable Python file contains the “pip install” command in the script. To resolve this error, you must use cmd or PowerShell to install any module using the “pip” package manager. To import the module you can use the “import” keyword in a program along with the name of the module. This article has presented a detailed guide on how to resolve the “SyntaxError: invalid syntax” in Python.

The pip package installer must be run from the command line. If you try to install a package from the Python interpreter or in a Python program, you’ll encounter the SyntaxError: invalid syntax error.

In this guide, we’re going to discuss the cause of the pip install invalid syntax error and what it means. We’ll walk through an example of this error so you can learn how to fix it in your code.

pip install invalid syntax

Python pip is a package installer. The pip tool lets you download and install packages from the Python Package Index, where thousands of libraries are available with which you can work in your code.

The pip tool runs as its own command line interface. pip is separate from your installation of Python. This is because pip is an installer rather than a tool that executes code.

If these tools were bundled together, it would be more confusing for developers who want to install packages because similar syntax used to start a Python program would also apply to installing modules.

This behavior is common across programming environments. Node.js relies on npm to install packages. To run a program using Node.js, you need to use the node command.

An Example Scenario

We’re going to set up the Beautiful Soup 4 library (bs4) in a development environment. This library lets you scrape a web page and retrieve particular pieces of data.

To start, let’s open up a Python 3 shell. In this shell, we’ll do all the work for our project:

python3


An interactive shell is opened in which we can write our Python code:

Python 3.8.5 (v3.8.5:580fbb018f, Jul 20 2020, 12:11:27)
[Clang 6.0 (clang-600.0.57)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>

Next, let’s import the bs4 library into our code. We must import any external libraries that we want to use before we can reference them in a program or the shell. Here’s the command we’ll use to import the bs4package:

>>> from bs4 import BeautifulSoup
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ModuleNotFoundError: No module named 'bs4'

Our code returns a ModuleNotFoundError when we try to import our package. This means that we can’t continue writing our program. Python cannot locate the package modules that we need to write our program. Let’s fix this error by installing the bs4 library:

>>> pip install bs4


This command results in another error:

File "<stdin>", line 1
	pip3 install bs4
    	^
SyntaxError: invalid syntax

It appears as if we cannot install bs4 using the pip3 command in the Python shell. pip3 is the package installer for Python 3 packages.

The Solution

We’ve tried to install the bs4 package from the Python interpreter.

You can tell because we’ve opened Python 3 using the python3 command and then we’ve executed the pip3 install command.

Python returns a pip install invalid syntax error because pip is not a keyword in Python. pip is a command line tool that must be run from a command line shell.

To fix this error, we must first exit our Python shell:

>>> exit()


The exit() command tells Python to close the interpreter that is open. Next, we can install bs4 from the command prompt:

pip3 install bs4


This command will install the pip library onto our system. Once this command has executed, we can open up a new Python shell:

python3 


Our new shell should have access to the bs4 library. We can test this by importing bs4 into our code:

>>> from bs4 import BeautifulSoup
>>> 

No error is raised. This means that the import was successful. We can now use bs4 in our program.

Conclusion

The pip install invalid syntax error is raised when you try to install a Python package from the interpreter. To fix this error, exit your interpreter and run the pip install command from a command line shell.

Now you have the expertise you need to solve this error like a professional coder!