Reference Guide  2.5.0
utils.py
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34 # Authors: A. R. Porter and R. W. Ford, STFC Daresbury Lab
35 
36 '''This module provides generic utility functions.'''
37 
38 import sys
39 
40 
41 def within_virtual_env():
42  '''
43  Utility function that identifies whether we are running in a Python
44  virtual environment. Works for virtualenv and Python 3's venv.
45 
46  :returns: True if we're running in a virtual environment.
47  :rtype: bool
48 
49  '''
50  # pylint: disable=no-member
51  return (hasattr(sys, 'real_prefix') or
52  (hasattr(sys, 'base_prefix') and sys.base_prefix != sys.prefix))
53 
54 
55 def a_or_an(string):
56  '''Returns 'an' if the supplied string starts with a vowel or 'h',
57  otherwise returns 'a'.
58 
59  :param str string: the string to check.
60 
61  :returns: 'an' if the supplied string starts with a vowel or 'h', \
62  otherwise returns 'a'.
63  :rtype: str
64 
65  '''
66  char = string[0].lower()
67  if char in ["a", "e", "i", "o", "u", "h"]:
68  return "an"
69  return "a"